TIJUANA (Mexico) • A peaceful march by Central American immigrants waiting at the south-western US border veered out of control on Sunday, as hundreds of people tried to evade a Mexican police blockade and run towards a giant border crossing that leads into San Diego.
In response, the United States Customs and Border Protection agency shut down the border crossing in both directions and fired tear gas to push back immigrants from the border fence. The border was reopened on Sunday evening.
The episode comes at a time of growing tension on both sides of the border and promised to become the newest flash point in the story of a caravan that was the target of US President Donald Trump's anti-immigrant rallying cry during the midterm elections.
Mr Trump has made preventing their entry into the United States a signature stance of his administration over the past few weeks, and has sent soldiers to the border.
Soon after the immigrants began their march to the border in Tijuana, they were met by Mexican federal police officers at a bridge that leads to the San Ysidro border crossing, through which millions of people and vehicles pass each year.
At that point, many of the marchers bypassed police by running across a dry riverbed.
Police, carrying riot shields, formed a new line and appeared to contain the rush of immigrants. They erected metal barriers on the roads and sidewalks.
A smaller group of immigrants tried to make their way to a train border crossing a few hundred metres away, where they were stopped by tear gas fired by US Customs and Border Protection officers. After the gas cleared, Mexican police officers pushed the protesters back from the area of the train crossing.
Homeland Security Secretary Kirstjen Nielsen said several immigrants who were trying to breach the fence had thrown projectiles at Customs and Border Protection officers. She said her department "will not tolerate this type of lawlessness and will not hesitate to shut down ports of entry for security and public safety reasons".
Officers arrested 42 people who managed to cross over from Mexico, chief border patrol agent Rodney Scott said yesterday.