Sara and Fernando Espinoza in Amsterdam in March 2018.

Her son had disappeared in Libya. Now she's trying to bring him home

(CNN)The phone call lasted just three minutes, but it gave Sara Espinoza the first proof in six weeks that her son is alive.

His voice was shaky, she said, almost unrecognizable from the confident commentary he would post to YouTube charting his foreign travels.
"Towards the end, I guess as they were telling him that the call had to end, he started crying," she said.
His final words were, "I'm sorry, but I have to go. And Merry Christmas."
Fernando Espinoza, a 29-year-old American teacher and former US Navy submariner, disappeared in Libya on November 9, five weeks after arriving in the country to start a new job at an international school in Tripoli.
He'd ventured south of the city for a weekend trip to a desert oasis, but on his return was picked up for questioning. And the frequent texts he sent to his mom ceased.
Sara had hoped to find her son and bring him home by Christmas Eve -- the date of Libya's first presidential election in a decade. But days out from the vote, the process has collapsed, pushing the country closer to conflict as warring parties seek to replace a government set to lose its mandate.
Now, Sara's more worried than ever.
"I'm relieved that I heard from him," she said of Tuesday's call, negotiated by the US embassy in Tunisia and Libyan authorities.
"But then I also feel very sad because I know that he's not well. My son never cries."
The US embassy told CNN after the call that inquiries were being handled by the State Department. When asked by CNN for comment on Fernando's status, the State Department said they were "aware of the detention of a U.S. citizen in Libya."
"We are monitoring the situation and due to privacy considerations, we are not going to go into specifics at this time," an official said.
After this story published, Libya's Deputy Foreign Minister Murad Hamaima told CNN Fernando had been detained because his visa had expired and he had left the city without permission to travel to a dangerous area.
"He violated his visa limitation, and he broke his contract with the school, and he left without telling anybody where he was going. I don't think this is acceptable anywhere in the world," Hamaima said.
He said Libyan officials would have deported Fernando sooner -- but when they asked if he he'd been fully vaccinated against Covid-19, Fernando said no, according to Hamaima. So he said they gave Fernando his first dose and were waiting ​the required amount of time to administer the second.
Back home in Miami, Sara doesn't know what to believe -- and has spent the past six weeks poring over any details of her son's trip in the hopes of bringing him home.
Fernando Espinoza graduated from the US Navy in 2012.

A weekend away

Sara had taken time off work to meet her son for a vacation in neighboring Tunisia this week, like they'd planned.
For many years, Sara raised Fernando as a single mother -- they're very close, he's her only child. And he's always had an adventurous streak, she said.
"He told me he's been to about 47 countries in about seven years or so," she said. "He's traveled a lot."
After being grounded during the pandemic, Sara said Fernando seized the chance to teach English in Tripoli at the International School of Martyrs or ISM International, a school for children from kindergarten to grade 12.
In early October, he flew to Libya and a month later, on November 4, he took a weekend trip to the Idehan Ubari desert to see the Gaberoun oasis, she said, a salty lake once home to a Bedouin tribe whose abandoned village is now a local tourist site.
From Tripoli, it's a treacherous trip south by roads that wind through areas vulnerable to attack by militias. The region is contested by multiple groups, and experts have warned it's unsafe to travel through.
Sara said she was told by ISM's administrator that Fernando had been explicitly told by his new employers not to venture outside Tripoli because it was too dangerous. But he went anyway.
Though Sara says she can see why Fernando went: "It's just part of his nature to be adventurous like that."
Fernando Espinzoa on another one of his trips -- to Brazil in February 2021.
Fernando hired a driver for ​the weekend trip, his mother said, nine hours south of Tripoli. From there, he would go to the desert oasis, about 58 miles (93 kilometers) ​west of the city ​of Sebha.
But Fernando didn't ​reach Sebha on time, according to text messages he sent his mom.
On the outskirts of Sebha, he and his driver were seized and held overnight, according to text messages Fernando sent to his mother on November 5.
It's not clear who held him, but he texted his mother to say he was fine.
November 5, 2021
I am free now
2:58 PM
100% safe. Just a huge misunderstanding
2:58 PM
Awesome, I'm so glad. How r u getting back?
2:59 PM
Airplane FOR SURE
2:59 PM
After his release, Fernando continued his trip to the oasis and sent a photo of himself looking happy and relaxed before dropping out of contact again.
That's when his mother really started to worry.
November 7, 2021
Nene, escribime (sic) cuando podas tener wifi otra vez. Besitos! (Baby, write me when you can get wifi again. Kisses!)
1:59 AM
Hola nene lindo adonde (sic) estas? (Hello beautiful boy where are you?)
8:08 AM
Good. Back from the desert. Spent the night there
10:21 AM
Oh ok that's what I thought. Did you have fun?
11:11 AM
Yes it was amazing. Super salty lake
1:00 PM
Fernando Espinoza described Gaberoun oasis as "amazing" in text messages to his mother and sent this photo of the lake.
It was the last time they texted together.​
Fellow English teacher Vanessa Powell said mutual friends had told her that Fernando was questioned and detained on his return by plane to Tripoli on November 9. ​Until his Tuesday phone call to his mom, none of his friends had heard from him in six weeks.
"He's not online. He's not on WhatsApp or messenger," Powell told CNN on November 30. "No one knows exactly where he is. We just have some kind of story that he's been arrested or is in jail or something."
Powell met Fernando several years ago in Iraq, and she said he briefly stayed with her in Cairo before he flew to Tripoli to start his new job. Fernando didn't express any concerns about his safety in Libya before he went, Powell told CNN, "because he's been doing this kind of work in developing countries for a while."