A group of about 50 “undocumented individuals” tried to storm a port of entry at the U.S. border with Mexico only to be pushed back by Customs and Border Patrol (CPB) agents using tear gas and pepper spray.

The attempted incursion occurred at the Pharr-Reynosa International Bridge about 4:00 a.m. on Saturday. Border Patrol agents say the illegals tried to rush across the bridge in 3 waves.

According to JP Media, the bridge is closed between midnight at 6 a.m., but CBP has had to construct temporary barriers in the middle of the span due to the large influx of migrants using the bridge at night.

A CBP official told Fox News the group attempted to rush across the bridge in three waves.

“Ignoring commands to stop, the group suddenly rushed the temporary barricades, bent metal poles and disabled the concertina wire affixed to the barrier,” the official said.

CBP officers, Border Patrol agents, Pharr police and members of the Texas Department of Public Safety were called upon to prevent the group’s entry, according to the official.

“Several males in the group disregarded commands to stop and physically pushed through the barriers,” the official said. “When confronted by CBP officers, the combative individuals began assaulting the officers by punching, kicking, and attempting to grab the officers’ protective devices.”

Two individuals were charged with interference and federal charges are pending against 14 others who were apprehended, the official said, adding that Mexican officials removed the remaining individuals from the bridge.

The bridge opened to commercial traffic at 8 a.m. after a two-hour delay.

This is not the first time a mob of illegal immigrants has tried to storm the border. According to NDTV News, US Border Patrol agents had to use tear gas and pepper spray to counter rock-throwing migrants when a group of about 150 tried to illegally cross the border from Mexico, earlier this year.

The Trump administration has mandated that asylum seekers remain in Mexico while their cases are heard in an effort to slow the flow of mostly Central American migrants to the southern border. The White House also said this week it was banning migrants from seeking U.S. protections if they pass through another country first, though that rule has been challenged in court.

Those policies and others that make it hard to seek asylum have led some migrants to cross the border illegally out of desperation, the Associated Press reported.

The Mexican government announced plans this week to spend millions of dollars to improve migrant shelters and detention centers that house families, but in southern Mexico, far from the U.S. border.