Since October, several caravans of Central Americans have been making their way toward the U.S. -Mexico border in hopes of claiming a credible fear of gang violence, governmental corruption or economic stagnation in their home countries.
The move by the parent's association of the elementary school came after US border agents fired tear gas into Mexico to turn back a group of migrants who had breached the border over the weekend. The network is the largest US owner of local TV stations by number of outlets.
The incident at the San Ysidro crossing marked an escalation of tensions that have been mounting since groups of Central American migrants began arriving in Tijuana a few weeks ago on their journey to attempt entry into the United States.
"We ran, but when you run the gas asphyxiates you more", Honduran Ana Zuniga told the Associated Press.
"All of us are having to pay for the actions of others", said Cristina Barrios, 44, of Guatemala, who said her 12-year-old daughter is suffering severe effects of an allergic reaction to the tear gas.
Reuters photographers captured children and their mothers as they fled from the tear gas.
On Sunday, a group of almost 1,000 migrants, dramatically attempted to storm the border fence, near Tijuana, Mexico, following the temporary closure of the Southern California border crossing.
After an incident at the southern border that saw U.S. Customs and Border Protection agents deploy tear gas against men, women and children seeking amnesty, Mexican officials are seeking answers about the use of these tactics.
McAleenan said four agents were struck with rocks but were not injured because they were wearing protective gear.
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Her children also were checked at a hospital and turned over to immigration authorities.
Three tear gas canisters shot from the US side landed around Meza and her children, who range in age from toddlers to teenagers, she said in an interview at a Tijuana migrant shelter.
Without offering more details, DHS officials said the vast majority of migrants are coming for "economic reasons and not asylum".
"I was scared, and I thought I was going to die with them because of the gas", said Meza. Some said they remained determined to cross, even after the results of Sunday's march to the border.
"We need Democrat votes to have a wall", Trump said.
Mexico's Interior Ministry said in a statement it would immediately deport those people arrested on its side and would reinforce security. "If they come here and there is a confrontation, we will be caught in the middle", she said. But it also includes people from South Asia, including India and Bangladesh, local media reports said.
According to the border forces, some of the asylum-seekers had thrown projectiles at them.
She said the parents worry about anti-migrant protesters converging on the sports complex again, as they did last week.
But it's also possible that Sunday's clash was borne of increasing desperation caused by the hardening of the policies, said Rachel Schmidtke, program associate for migration at the Woodrow Wilson International Centre for Scholars Mexico Institute.
Unlike the composition of those who cross illegally, citing Homeland Security's own data, the study said recent statistics indicate that those who overstay their visas are overwhelmingly from other countries.