WATCH: Tijuana mayor declares humanitarian crisis as 5,000 migrants enter town

WATCH: Tijuana mayor declares humanitarian crisis as 5,000 migrants enter town

Transcript for Tijuana mayor declares humanitarian crisis as 5,000 migrants enter town

On this holiday weekend the president is talking about another subject. He’s keeping the spotlight on one of the central issues, immigration. He’s now threatening to shut down the entire southern border with Mexico. The trigger for that, the situation in Tijuana where the mayor is now declaring a humanitarian crisis with 5,000 migrants from the so-called caravan now gathering there trying to get into the U.S. ABC’s white house correspondent Tara Palmeri is in west palm beach where president trump is spending the holiday weekend. Good morning, Tara. Reporter: Good morning, Eva. After a month-long journey, the caravan of migrants is finally at the U.S. Border. Along the way, locals have offered them food and shelter but now that they’re in this border town of Tijuana, they say they can’t handle the crowds and they’re at capacity. Overnight a crisis at the border. The mayor of Tijuana requesting aid from the united nations as nearly 5,000 Central American migrants wait to apply for asylum in the U.S. Fleeing violence and poverty, a group of migrants from Honduras waving flags and demanding to be let into the United States. The town’s food and shelter pushed to the limits as migrant mothers and their children huddle under blankets feet away from the edge of the U.S. Border. All this as the president threatens to shut down the border. We will close entry into the country for a period of time until we can get it under control. The entire border? The whole border. I mean, the whole border. Reporter: The president not stopping there raising the possibility of allowing U.S. Troops to use lethal force. They have to, they’re going to use lethal force. I’ve given the okay. I hope they don’t have to, but, you know, you’re dealing with a minimum of 500 serious criminals so I’m not going to let the military be taken advantage of. I have no choice. Do I want that to happen? Absolutely not. Reporter: Secretary of homeland security kirstjen Nielsen said that there are 500 serious criminals and gang members in this caravan, but when asked what crimes they committed and how they identify them, she gave no evidence. Dan. All right, Tara Palmeri reporting in from Florida. Tara, thank you. A lot to talk about this morning, so let’s bring in our chief political analyst, Matthew dowd. Good morning. The president, as we just saw, threatening to shut down the entire southern border over these migrants. To you does that sound reasonable or even feasible? Well, much with president trump is not always reasonable or feasible, but I think this is what the president has been talking about for the last month and a half. He’s obviously — he’s recently threatened to shut down the government if he doesn’t get his border wall. I think almost the — this is exclusive humanitarian problem, not a security problem and if the president wanted to do something about security, there was much more violence happened as the start of the show said at malls of America on Black Friday than it has at the border, so I think this is just another political message he’s trying to send to his base of voters that are concerned about immigration. Let me loop back for a moment to Jerome Corsi, who we heard about in the story that David Wright brought us just a few moments ago. Corsi is an associate of president trump, also an associate of Roger stone. Corsi is now reportedly in plea negotiations with the special counsel Robert Mueller. How much of it — we don’t know the details of these negotiations, but based on what we know, how much of a threat does Corsi pose to the president, if any? Well, I think the entirety of the Mueller investigation is a threat to the president and a threat to the president’s family and a threat to many people around the president. If I was the president I’d be worried as Bob Mueller wraps this up and will present a report to the justice department and congress will get it. This is a big threat to him and to the ongoing ability of his administration to function. If I were Roger stone, I’d be very concerned because Roger stone hasn’t been called before any grand jury, and he seems to be a target of this, so it would be a big concern. Matthew dowd reporting in from Texas on a Saturday morning. We really appreciate it. Dan. Yes. Dan, you didn’t ask me the best, most important question. Michigan/ohio state, that’s today. Michigan/ohio state. Well, consider it asked. What is your answer? Let me give you a clue. Hail to the victors valiant, hail to the conquering heroes, go, Michigan. Okay, I wouldn’t have gotten the clue until you said Michigan. And all the people from the Ohio state university. Glued to his TV all day today. Making friends all over the buckeye state, Matthew dowd, we appreciate it. Thank you, sir.

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

Read More