Federal officers at the country’s busiest land port of entry, located on the California-Mexico border, prepared this week for potential major disturbances as the Biden administration grapples with an influx of people illegally crossing the border.

Vehicles and pedestrians traveling back and forth between Tijuana and San Diego on Wednesday saw clouds of smoke and heard loud noises at the San Ysidro Port of Entry. Officers were outfitted with helmets, large firearms, less-lethal devices, and shields.