So-called "stash houses" or "drop houses" are all over Phoenix, Arizona. These are buildings that human smugglers use to hide illegal immigrants.
I've come here to meet Alonzo Pena, the special agent in charge of the Immigration and Customs Enforcement office in Phoenix. We're about to take a drive around the city to see some of these stash houses.
But first, Agent Pena shows me a city map with little red dots showing where these houses are located. The map is peppered with so many dots that it looks like it's been used in target practice at a firing range. In the first four months of this year, authorities say they have discovered nearly 80 new stash houses.
This highlights a disturbing trend in how human smugglers, or "coyotes," as they are often called, are operating these days. Coyotes are no longer just a border phenomenon, according to federal law enforcement authorities. They're organized like drug cartels and getting more viscious and lethal. And they're moving further north into the United States. (In Houston, one person was killed and two others wounded in a recent midday shootout; federal authorities say rival coyotes may have been fighting over a carload of illegal immigrants.)
Agent Pena says these smugglers fight each other over "loads" of immigrants mostly because there's big money at stake. Coyotes charge Mexican nationals a $1,500 smuggling fee, according to law enforcement officials and immigration activists. For people south of Mexico, the fee ranges from $3,000 to $5,000. Of course, coyotes will often "renegotiate" later, and that's when things can get really ugly.
Agent Pena and I pull up to a beautiful stucco home with a Spanish tile roof. You would never suspect the house was used by smugglers. "I wouldn't mind living in a house like this," Pena says. His agents found 160 illegal immigrants stashed in this house.
-- By Ed Lavandera, CNN Correspondent