Transcript for US agents reportedly using tear gas at the Tijuana border

We turn to the other breaking news we're monitoring from the border where thousands of migrants from that caravan have arrived. Some of them breaking through Mexico's police lines in Tijuana surging into the no man's land between the two countries. U.S. Agents reportedly responding with tear gas and completely shutting down the busy crossing near San Diego. The army now reporting members of the military are on the scene. ABC's Marci Gonzalez is there. Reporter: Tonight chaos erupting on the border, hundreds of migrants rushing to cross into the U.S. From Mexico. The group, mostly men pushing past Mexican authorities in riot gear, climbing over barricades. One group attempting to climb on top of this train where they were confronted by Mexican police. At one point migrants retreating after reports of border agents throwing tear gas canisters. This video showing migrants running through traffic at the entrance to the border. The us border patrol shutting down the San ysidro port of entry to cars and pedestrians. It's unknown if anyone made it across. Additional officer deployed to stave off the crowds. It is a tense situation here. Mexican police in riot gear pushing migrants back. They are yelling at officers angry because they say the tear gas injured two children. The latest clashes come after continued threats by president trump to Mexico. We will close entry into the country for a period of time until we can get it under control. For the entire border. The whole border. I mean the whole border. Reporter: This morning senators from his own party responding. We would prefer to keep it open, so let's work really hard to make sure we're addressing the asylum seekers before they actually come over the border. That's the intent of the president, to divert any issues before they actually happen. So, of course, we don't want to see the border closed. But, do you know what? Safety of our nation comes first. Reporter: This morning trump again blaming Democrats for the Central American caravan tweeting -- would be very smart if Mexico would stop the caravans long before they get to our southern border, or if originating countries would not let them form. No crossings! Tonight as the border grows more unruly, and officers stand their ground. Tijuana's mayor calling it a humanitarian crisis, as questions increase looking for solutions to calm the situation. And tonight U.S. Customs and border patrol saying as of now that port of entry must remain closed and everyone trying to cross illegally through those vehicle lanes was sent back.

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