Border Patrol agents in a California mountain range were fired upon from Mexico while taking a group of migrants found illegally entering the country into custody last week – another instance of violence against U.S. immigration officers at the border, yet no arrests have been made. 

At approximately 9 p.m. on Aug. 9, Border Patrol agents "were the target of multiple shots" near Otay Mountain, which contains the highest summit of the San Ysidro Mountains in San Diego County, according to a statement released Saturday by U.S. Customs and Border Protection. 

The barrage of bullets was unleashed on agents arresting a group of undocumented immigrants, about two miles east of the Otay Mesa gatehouse and approximately 250 yards north of the international border. As agents escorted the group to their vehicles, they heard gunfire and gunshots heading toward the area where they were, U.S. Customs and Border Protection said.

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Agents immediately ordered the migrants to take cover behind the bushes, while they themselves sought shelter. Marine Air Operations (AMO) and the tactical unit (BORTAC) responded to the area immediately, but could not locate the subjects, the statement, initially issued in Spanish, said. 

The international liaison unit requested the assistance of Mexican authorities, who responded south of the border in the area where the shots were suspected to originate, according to U.S. Customs and Border Protection. Residents of the area reported seeing several people from the Mexican side flee the area in a pickup truck and a motorcycle. No other information on the subjects could be obtained.

"Border violence is a serious threat to public safety, and to border agents responsible for national security. This incident is another example of the dangers our officers face every day." San Diego Sector Border Patrol Chief Aaron Heitke said in a statement. "We are taking this event very seriously."

The shooting is under investigation and patrols in this area have increased. Anyone with information about the shooting is asked to call the San Diego Sector Intelligence Center at (619) 216-4180.

The California incident happened just three days after another shooting was reported by Border Patrol agents in El Paso, Texas. Surveillance camera operators in that sector confirmed the presence of two subjects armed with high-caliber rifles firing toward the North American side of the Rio Grande.

The number of people encountered illegally crossing the U.S.-Mexico border has reached the highest in 21 years, after nearly 213,000 migrants were stopped in July alone, Homeland Security Secretary Alejandro Mayorkas said at a press conference in Brownsville, Texas, on Thursday. That's nearly three times as many found in between the ports of entry at the southern border in January, when President Biden first took office. 

Meanwhile, border communities such as Laredo, Texas, are also encountering a record breaking number of stash houses, where cartel smugglers work with local gangs to crowd migrants in anything ranging from trailers to residential homes in neighborhoods, often leaving them sharing one bathroom and packed together in soaring heat until they can be loaded into trucks to be transported further north.  

Since the start of the fiscal year in October, more than 5,000 illegal immigrants have been found at stash houses in Laredo, located in Webb County on the north bank of the Rio Grande. Laredo Mayor Pete Saenz, a Democrat, told the Washington Examiner local law enforcement officers are desperate for more federal resources, including more Border Patrol agents. Investigator Jose Baeza, a 22-year veteran of the Laredo Police Department, said stash houses have long existed but never at this volume. 

Compared to other areas where families or women and children are found attempting to seek asylum, 96% of migrants arrested in the Laredo region are adults, as stash houses usually hold adult men with criminal records or who have been deported before resorting to pay smugglers thousands of dollars to attempt to evade U.S. Border Patrol. 

Stash houses bring further violence to the community. 

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Last month, a 17-year-old girl attempting to alert authorities about one stash house was kidnapped at gunpoint by two suspected cartel members, who tortured her for five hours, pouring gasoline and salt into wounds they inflicted upon her, the Laredo Morning Times reported, citing an arrest affidavit. Besides being tipped off by community members, police sometimes also find stash houses if the migrants inside dial 911 out of desperation if their smugglers have left them for days without food or water. 

Still, many stash houses are not found by authorities. Video obtained by KGNS last week showed a parked tractor-trailer just off the highway as dozens of migrants, including men, woman and possibly children, are seen rushing toward the vehicle and clamoring to get inside to claim a spot.