Tucson, Arizona (CNN) -- A mother and daughter lean against the bus station wall, huddled together under a cream-colored blanket. Their eyes droop as exhaustion sets in.
They spent the past few days in detention, and Ana Maria worries about what the future holds.
But even as questions swirl in her head, this 28-year-old mother says one thing is certain: "I do not want to go back to Guatemala."
It's been three years since she last saw her husband, who works in a restaurant in Portland, Oregon. Now he's just three bus rides and 34 hours away.
She's excited to bring her family back together, find a job that pays well and watch her 10-year-old daughter Greisy succeed in school.
"We came here," she says, "to fight."
Ana Maria and Greisy are part of a surge of mothers and children from Central America who authorities say are illegally crossing the border into the United States.
Dozens of them file through the Tucson bus station daily, carrying papers stamped with the date they could be deported.
Everything is up in the air. The only thing they know for sure is where they're going next.
If they were Mexican, it's likely officials would have swiftly deported them back across the border. And if the federal government had more space to hold undocumented families, they could still be in detention.
Instead, officials have been releasing these mothers and children on parole, dropping them off at bus stations like this one and giving them a month to report to immigration offices around the country.
It's a dramatic scene playing out across Arizona and Texas as the number of people from Guatemala, Honduras and El Salvador crossing the border grows.
At the Tucson station, it started in September with a few people trickling in each day. Now the numbers have grown so much that volunteers come here daily, too, spending hours handing out donated clothes, food and supplies for the journey ahead.
America's newest undocumented immigrants ask them a chorus of desperate questions.
Where are we? How do I buy a ticket? Can you help me make a phone call? Do you have diapers? Is there a sweater that would fit my daughter? Do you have pills for stomach aches?
Is it cold on the bus? How will I know when I need to get off? Will I be able to find work here? Do I have to send my children to school?
After weeks of helping out at the bus station, many volunteers have responses at the ready.
But there's one question they can't answer.
Are they going to send us back?
'A lot of hunger'
Maria Eugenia Carrasco takes stock of the supplies in a donation area she and other volunteers maintain at the bus station as she prepares for women and children to arrive.
"We need fruit," she says. "The ones yesterday came with a lot of hunger."
As she rushed to heat up cups of soup for them in the station's microwave, she says one woman told her not to worry.
"Back home," the woman said, "there are also days when we don't eat."
Carrasco wishes politicians would take time to hear the things she hears, learning about the social and economic forces that push people to risk their lives and immigrate to the United States.
"They speak about immigration as a cause and not as an effect. But immigration is an effect of another cause," she says. "This isn't a trip to Disneyland. They have to feed their families."
A worried call
A woman from Honduras borrows a cell phone from a volunteer to call her husband in Maryland. She's trying to work out the details of buying a bus ticket and tells him about the time she spent with their daughter in detention.
"They just gave a cracker and a juice every day to the girl," she says. "They gave me less."
It was cold inside, she says, and they slept on the floor.
He sounds worried. She tells him to relax.
"I've had to have a lot of patience, too," she says.
She asks him to call her mother.
"Tell her that we are OK."
No end in sight
Sometimes they're caught after slipping across the border in the dark of night. Other times they surrender at border crossings.
Once they're apprehended, the undocumented mothers and children are brought to detention facilities at Border Patrol stations for processing, which can take days. Last month, so many mothers with children were caught crossing in South Texas that nearby processing centers couldn't handle the volume. So federal authorities flew hundreds of people to centers in Arizona.
That's when numbers at the Tucson bus station surged. On some nights, volunteers say, immigration officials dropped off more than 70 people.
The practice of bringing people from Texas, which drew sharp criticism from Arizona leaders like Gov. Jan Brewer, seems to have stopped for now, volunteers say.
But there's still a steady stream of women and children from Central America arriving in Tucson. Most of them say they crossed the border in Arizona. Many, particularly groups from Guatemala, say someone in their country told them they would be able to stay in America and work if they brought their children with them.
Combined with an alarming trend of Central American children crossing the border alone, the arrival of these mothers and children has sparked a political firestorm.
Critics question whether the Obama administration's policies are fueling this latest wave of illegal immigration. They accuse the government of taking a "catch and release" approach that doesn't do enough to crack down on undocumented immigrants.
Why are authorities releasing the mothers with children on parole? Officials say it's a simple matter of math. The government has only one family immigration detention center, in Pennsylvania, and it doesn't have the capacity to hold the large number of so-called "family units" coming across the border, officials say.
On Friday, the White House announced the government would soon be taking a more aggressive tack, expanding the number of detention facilities that house family units and stepping up efforts to process their cases.
It's not clear yet how authorities will ultimately handle the surge in cases from Central America. Officials can keep extending humanitarian parole indefinitely, Tucson immigration attorney Maurice Goldman says, or press to place deportation cases in the hands of immigration judges.
Authorities haven't revealed how many immigrants have been released on parole -- or how many of those released on parole have showed up at their meetings with deportation officers.
As politicians debate policy, at this bus station thousands of miles from Washington but just over an hour's drive from the Mexican border, there's no end in sight.
"We don't know what's happening from one week to the next," volunteer Laurie Melrood says. "We never know what the next day will bring."
A jarring explanation
A group of women sit on blankets on the floor in a screened off area of the bus station where volunteers have brought in bins of clothing and bags of food. The women seem stunned, and angry.
They left detention with a packet from Immigration and Customs Enforcement. Melrood has just explained what the papers say, and it isn't what the mothers wanted to hear.
She tells them the drill: They have a meeting with a deportation officer in a month. Their parole ends in September. After that, they could find themselves in a deportation hearing.
"It is not fair to deport us," one woman says. "We came because of poverty."
Another woman says she agreed to pay smugglers thousands of dollars to get her and her children to the United States from Guatemala. It's money she doesn't have, and was planning to earn working here.
"How could they only give us three months to pay our debt?" she says.
It's a difficult conversation to have, particularly since many of the women appear to arrive at America's doorstep thinking there's an easy path that will let them stay in the country and work.
Not so, Melrood says, advising them to look for immigration lawyers as soon as they arrive at their destinations, to help navigate the system and plead their case.
"It's better to tell them up front," Melrood says. "We say, 'We're not making your decision, but this is the truth,' so that we don't sugarcoat something or extend that mythology."
From training to triage
Karen Sisco smiles as she looks at Ana Maria and Greisy's lengthy bus itinerary and sees the final destination.
"Oh, that's in Portland," Sisco says, "where my daughter is."
Today is Sisco's first day volunteering at the station. The retiree had been hearing news reports about the growing number of immigrants passing through, and she jumped at the opportunity when a local newspaper gave details about how to help.
"For people who have traveled so far, with nothing to their names, I just want to show them some humanity, some kindness," she says. "I love children, and I'm a mom. I just can't imagine the pain, the suffering and the fear."
Beth Lowry, who's been coordinating volunteers at the station for weeks, is training Sisco. She shows her how to decipher complicated bus itineraries. She points out where they keep bags of food and toiletries to hand out. And she tells her the solution to most of the medical problems that pop up among arriving immigrants: Pedialyte, which helps them bounce back quickly from dehydration.
But it's not long before the training session turns into triage. A new wave of mothers and children suddenly arrives. They look lost and lethargic. Sisco starts heating cups of soup.
"Thank you," one woman tells her. "We haven't eaten in a long time."
A refuge, for now
While other women around her look worried, Zelma says she finally feels safe.
She's here with her 16-year-old son, her 5-year-old daughter and her 1-year-old baby.
Gang violence forced them to flee Honduras, she says. Neighborhood thugs wanted her son to become one of their enforcers, collecting so-called "war tax" payments from local businesses.
He refused, but they wouldn't take no for an answer. Gang members beat and stabbed him, she says, and police were unsympathetic. "The official said, 'What do you want us to do about it? I can't give your son a bodyguard.'"
When her son kept refusing to join, the gang lobbed another threat: "If he doesn't join us, we'll kidnap all the girls in your family."
The family was terrified, she says, and called her brother, a waiter in New York, to ask him to send money to help them get out of the country.
She was scared to leave Honduras, but says she's amazed by the kindness from strangers at the bus station and looking forward to starting a new life with her family.
"There are good people," she says as a volunteer hands her a pacifier for her baby. "We have had a lot of luck along the way."
Catalina Campo Llamas cries after speaking with several women in the station's waiting area.
"This hits very close to my heart," she says.
Thirty years ago, Campo left Mexico and crossed into the United States through the desert.
"People found me. They gave me food and clothes," she says. "They saved my life."
A ranch hand led her and a friend to safety, bringing them to a home where a woman gave them long-sleeved shirts, shoes, soup and her first-ever glass of iced tea. She still remembers how delicious it tasted.
She was a terrified 16-year-old then without even a passport to her name, running away from a life of poverty. Two years later she was among millions of undocumented Mexican immigrants who received amnesty from the Reagan administration and became legal residents.
Now she's a U.S. citizen who's built a life for herself north of the border, and it's something she says she never could have accomplished without the kindness of strangers.
Hours earlier, she told her story at Tucson's Prince of Peace church and reminded her friends there that people at the bus station needed help.
Moved by her words, the congregation banded together to prepare food.
Now Campo and several others are handing it out at the station.
On bags filled with homemade burritos, there are smiley faces drawn beside a handwritten message in English: "Someone cares."
In the waiting area, the church volunteers and immigrants join hands in prayer.
"We ask you to protect them on their journey," the prayer begins.
It ends with a message of love: "We are all brothers and sisters."
A Honduran boy with spiky hair and sunken eyes points at his left eye and says it hurts. His mother says she thinks it's a sign of exhaustion after days of sleeping on the floor in detention.
Within seconds, Melrood is on the phone seeking medical advice from a doctor who gives regular consultations to volunteers at the station.
"There's a boy here that might have pink eye, it looks like," she says in English. "He's 5 years old and he looks like he came out of a concentration camp."
She hangs up the phone and slips into Spanish to speak to the boy.
"If your eye hurts, tell your mother," she says. "Don't touch it."
Why the influx?
On a recent Saturday night, more than a dozen families from Guatemala take up nearly half the seats in the small station's waiting area.
It's a surprising sight for Miguel Leon, who immigrated to the United States in the early 1990s to escape Guatemala's brutal civil war. He had survived a massacre that left six members of his family dead.
That war is long over, but Leon says the number of people he sees coming to the United States now seems similar.
"It looks like this is turning again into the same situation," he says.
Observers have different theories about why so many Guatemalans are coming to the United States.
Some speculate that organized crime groups are pushing people out so more land will be available for criminal enterprises. Others say crafty smugglers are spreading a misleading message about U.S. immigration policy to people desperate for options.
Jimena Diaz, Guatemala's consul general in Phoenix, says a variety of social and economic forces are at play, but there's one above all: Families want to reunite.
"People always came," Diaz says, "but never this quantity."
Blankets and books
In the past month, hundreds of Guatemalans have arrived at bus stations in Tucson and Phoenix alone, according to Diaz. With no sign of the numbers slowing, she says, officials are working to come up with a more detailed system for tracking their cases. And Diaz regularly stops by the Tucson station to check on the situation.
She advises mothers to keep their immigration appointments, even if they're tempted to skip out. Otherwise, the consequences can be dire.
Even if someone makes it five or six years without detection, she tells them, something as simple as a burned-out tail light could lead to deportation.
Volunteer Dianne Ruiz De Quijada approaches her with a problem.
"We don't have any more blankets," she says. "I had to cut the big one in half."
Diaz checks her car to see if she has any, but comes up empty.
Instead she brings inside some children's books she found in a donation bag.
"Do you like to read?" she asks, handing out books to groups of giggling kids at the station. "So you can learn English."
She gives a young boy beside her a book called "USA."
A mother in chains
All day, the biting chill of cranked-up air conditioning fills the bus station.
At night, it seems even colder.
Gone are the volunteers who brought food and laughter.
Six women and children remain huddled in a row of chairs. A janitor mops the floor around them as they wait for the last bus.
A 26-year-old Guatemalan mother's eyes well up with tears as she talks about the past few days. She says she doesn't want her name used, fearing it could hurt her case when she goes to immigration court.
Her 7-year-old daughter seems happy now, bounding around the station with pigtail braids and a floppy-sleeved blue sweatshirt from the donation pile that's adorned with a bright pink butterfly.
But her mother can't shake the memory of their days in detention.
"My daughter cried for two hours seeing me in chains. She said to me, 'Why are you like that?' It was very hard, very hard," she says. "I thought it was going to be easy. If I had known, I never would have come. These are things that you remember all your life. You never forget."
Nearby, Sbhavana Arora's eyes are red and her voice trembles.
"I don't know if I'm happy or sad," she says softly. "Please pray for me."
She has come to the United States to seek asylum and is heading to a shelter in Texas where she hopes she can get help. Religious violence forced her to flee India with her husband, she says.
While almost all the immigrants who pass through the Tucson bus station are from Central America, volunteers say they've seen mothers and children coming from other regions, too.
For four years, Arora and her husband lived in Peru, trying to earn enough money to take refuge in the United States.
Days ago, they finally crossed the U.S.-Mexico border with their 3-year-old daughter. But authorities took her husband to a different detention center, and now she doesn't know how to reach him, or whether he'll be released.
"Right now I feel so helpless," she says. "We came here for help, but I don't know if we will get it."
The world in their hands
The station's loudspeakers announce that the 11:40 p.m. bus for El Paso has arrived. It's the last bus of the night -- the route taken by many immigrants passing through the station as they head east to reunite with family.
As they wait to board, Arora sings to her daughter, "The wheels on the bus go 'round and 'round." The girl won't stop crying and asking where her father is.
Tonight, almost everyone lining up for the bus is an immigrant.
One by one, they hand over their tickets to the driver and walk outside, carrying small bags that hold all their possessions.
The bus pulls out of the station just after midnight.
A new journey has begun.