U.S. Border patrol agents are firing tear gas at migrants after a group attempted to breach the border,  the Associated Press reported Sunday.

Migrant children and their families were sent running after the police attack. Twenty-three-year-old Honduran migrant mother, Ana Zuniga, told AP some migrants managed to cut a small hole in the wire fence bordering Mexico which triggered police action from U.S. agents.

“We ran, but when you run the gas asphyxiates you more,” she said.

Hundreds of caravan members including women and children protested peacefully on Sunday with chants of “We aren’t criminals! We are hard workers.” As they neared the U.S. border, they were stopped by Mexican authorities, who told them to wait for permission. 

Groups of migrants, some of them bearing the Honduran flag, broke off and headed toward the border fence, where U.S. Customs and Border Protection officers gathered on the other side, backed by U.S. military police, San Diego police and the California Highway Patrol.

An average of 70,000 vehicles and 20,000 pedestrians cross from Mexico to the United States at San Ysidro each day, according to the U.S. General Services Administration.

However, traffic has been stalled in both directions in San Ysidro in a "drastic response" closure which would cost "millions of dollars," Duncan Wood, director of the Mexico Institute at the Wilson Center research group in Washington, noted.

U.S. President Donald Trump tweeted on Saturday that migrants at the U.S.-Mexico border would stay in Mexico until their asylum claims were individually approved in U.S. courts, but Mexico's incoming government denied they had struck any deal.

U.S. and Mexican negotiators met on Sunday to discuss a plan to keep the Central Americans in Mexico during this time. Normally, asylum-seekers announce their intention on arriving at U.S. ports of entry or after crossing the border illegally.