Mexico's Interior Ministry said Sunday it would immediately deport those who tried to "violently" enter the U.S. from Tijuana. Meanwhile, Tijuana's municipal government said that more than three-dozen migrants were arrested for disturbing the peace and other charges stemming from the march and what followed.
The vast majority of the more than 5,000 Central American migrants camped out for more than a week at a sports complex in Tijuana returned to their makeshift shelter to line up for food and recuperate from an unsettling afternoon.
Lurbin Sarmiento, 26, of Copan, Honduras, walked back to the sports complex with her 4-year-old daughter shaken from what had unfolded a short time earlier at the Tijuana River and U.S. border.
She had been at the bottom of the river, a concrete riverbed conveying a trickle of water, near the border with her daughter when U.S. agents fired tear gas.
"We ran, but the smoke always reached us and my daughter was choking," Sarmiento said.
She said she never would have gotten that close with her daughter if she thought there would be gas.
The gas reached hundreds of migrants protesting near the border after some of them attempted to get through the fencing and wire separating the two countries. American authorities shut down the nation's busiest border crossing at San Ysidro for several hours at the end of the Thanksgiving weekend.
The situation devolved after the group began a peaceful march to appeal for the U.S. to speed processing of asylum claims for Central American migrants marooned in Tijuana.
Mexican police had kept them from walking over a bridge leading to the Mexican port of entry, but the migrants pushed past officers to walk across the Tijuana River below the bridge. More police carrying plastic riot shields were on the other side, but migrants walked along the river to an area where only an earthen levee and concertina wire separated them from U.S. Border Patrol agents.
Some saw an opportunity to breach the crossing.
An Associated Press reporter saw U.S. agents shoot several rounds of tear gas after some migrants attempted to penetrate several points along the border. Mexico's Milenio TV showed images of migrants climbing over fences and peeling back metal sheeting to enter.
MIGRANT CARAVAN: Life with the migrant caravan in Tijuana, Mexico
Honduran Ana Zuniga, 23, also said she saw migrants opening a small hole in concertina wire at a gap on the Mexican side of a levee, at which point U.S. agents fired tear gas at them.
Children screamed and coughed. Fumes were carried by the wind toward people who were hundreds of feet away.
"We ran, but when you run the gas asphyxiates you more," Zuniga told the AP while cradling her 3-year-old daughter Valery in her arms.
As the chaos unfolded, shoppers just yards away on the U.S. side streamed in and out of an outlet mall, which eventually closed.
Throughout the day, U.S. Customs and Border Protection helicopters flew overhead, while U.S. agents on foot watched beyond the wire fence in California. The Border Patrol office in San Diego said via Twitter that pedestrian crossings were suspended at the San Ysidro port of entry at the East and West facilities. All northbound and southbound traffic was halted for several hours. Every day more than 100,000 people enter the U.S. there.
Department of Homeland Security Secretary Kirstjen Nielsen said in a statement that U.S. authorities will continue to have a "robust" presence along the Southwest border and that they will prosecute anyone who damages federal property or violates U.S. sovereignty.
"DHS will not tolerate this type of lawlessness and will not hesitate to shut down ports of entry for security and public safety reasons," she said.
More than 5,000 migrants have been camped in and around a sports complex in Tijuana after making their way through Mexico in recent weeks via caravan. Many hope to apply for asylum in the U.S., but agents at the San Ysidro entry point are processing fewer than 100 asylum petitions a day.
Irineo Mujica, who has accompanied the migrants for weeks as part of the aid group Pueblo Sin Fronteras, said the aim of Sunday's march toward the U.S. border was to make the migrants' plight more visible to the governments of Mexico and the U.S.
"We can't have all these people here," Mujica said.
Tijuana Mayor Juan Manuel Gastelum on Friday declared a humanitarian crisis in his border city of 1.6 million, which he says is struggling to accommodate the crush of migrants.
U.S. President Donald Trump took to Twitter on Monday to express his displeasure with the caravans in Mexico and to make another pitch for his promised border wall.
"Mexico should move the flag waving Migrants, many of whom are stone cold criminals, back to their countries," Trump tweeted. "Do it by plane, do it by bus, do it anyway you want, but they are NOT coming into the U.S.A. We will close the Border permanently if need be. Congress, fund the WALL!"
Trump has repeatedly suggested without evidence that the migrant caravans are full of hardened criminals, but they are mostly poor people with few belongings who are fleeing gang violence. During his presidential campaign, he promised he'd have Mexico pay for the wall.
Mexico's Interior Ministry said Sunday the country has sent 11,000 Central Americans back to their countries of origin since Oct. 19, when the first caravan entered the country. It said that 1,906 of those who have returned were members of the recent caravans.
Mexico is on track to send a total of around 100,000 Central Americans back home by the end of this year.
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