Transcript for Border Patrol begins processing migrants from caravans

Now the latest on that crisis at the border where a caravan with more than 100 immigrants are seeking asylum. Overnight customs began processing some of those immigrants, mostly mothers and children and Matt Gutman is on the scene. Good morning to you, Matt. Reporter: Hey, good morning. That first batch of eight asylum seekers is right now being processed in the border terminal behind me. It is a legal process and it can last for years and for many of these people it hinges on something called a credible fear interview, basically they have to prove to agents that they face persecution if they would be sent back home and many are, in fact, sent back home. Right now the 150 or so other migrants you're seeing here, they're hunkering down. They've set up a tent city here. There is a kitchen over there and what you're seeing here is an act of defiance because Mexican officials have told them to go to a shelter. They are saying they'll stay here as long as it takes. They say after a month on the road and 2,000 miles of a trek sleeping on the concrete so close to the U.S. Border isn't that bad, Michael. Matt, we should note it is totally legal to seek asylum. Reporter: That's right. It is legal to seek asylum and many people are denied asylum. But, you know, I have a been to many of these countries where this happens from talking to these people here, they say they fear from gangs who have either killed their family members or are threatening them, in fact, a U.S. Study put out a couple of years ago said 82% of female asylum seekers face a credible fear of persecution or sexual violence against them so for many of these people the stakes are incredibly real. Michael. All right, Matt, thank you so much for your report.

This transcript has been automatically generated and may not be 100% accurate.