A U.S. Border Patrol agent has shot and killed an apparently undocumented migrant who allegedly threw rocks at the agent , striking his face , on the California-Mexico border near San Diego , authorities said . A social justice advocacy group on Wednesday criticized the Border Patrol 's use of deadly force in the Tuesday incident , saying there 's a disturbing trend of Border Patrol `` killings of rock throwers , some of whom were teenagers and some whom were U.S. citizens '' on the U.S.-Mexico border , said Andrea Guerrero , executive director of Alliance San Diego . The Border Patrol declined to comment directly on this week 's incident , which is under investigation by local authorities , but in the past , the agency has highlighted how agents are seriously injured in rock-throwing incidents and resort to lethal force to protect themselves . Guerrero said , however , some police experts advise using nonlethal force such as pepper-ball guns to respond to rock throwings . `` Border agents should adhere to best policing practices and only use lethal force as a last resort , not the only resort , '' Guerrero said . In the San Diego sector on the U.S.-Mexico border , the Border Patrol has recorded more than 400 assaults , including rock throwings , on agents since 2010 . The numbers have fluctuated in recent years , from 130 assaults in 2010 , 77 in 2011 , 133 in 2012 to 73 in 2013 , according to the agency 's statistics . Names of the agent and the apparently undocumented migrant in this week 's deadly encounter have n't been released by authorities . Rock-throwing incidents have been controversial on the U.S.-Mexico border , particularly when Mexicans have thrown projectiles from the Mexico side of the international line toward Border Patrol agents on the U.S. side . In some cases , U.S. Border Patrol agents have fired their guns at the rock throwers on the Mexico side of the border , killing the rock thrower . Mexican officials have condemned the Border Patrol 's use of lethal force as excessive . The U.S. Border Patrol said the incident occurred in a rugged section of the Otay Mountains near San Diego where the agent was trying to arrest several immigrants who crossed the border illegally . `` During the attack the agent was struck in the head with a rock , '' the Border Patrol said in a statement . `` Fearing for his life the agent discharged his service issued weapon resulting in the death of one assailant . '' Two other undocumented migrants were arrested and in custody , the agency said . The San Diego County Sheriff 's Department , which is investigating the killing , said in its account that two Border Patrol agents were trying to detain a group of suspected undocumented migrants in rugged terrain in the mountain 's White Cross area about four mile east of the Otay Mesa border crossing . `` The two agents were out of sight of each other when one of the agents was struck in the face by a rock thrown by one of the suspects , '' Lt. Glenn Giannantonio said in a statement . `` Fearing for his safety , the agent fired his duty pistol at the man , striking him . The man was pronounced dead at the scene . '' The border patrol agent who fired his service weapon suffered minor injuries , the sheriff 's homicide unit said .
A Border Patrol agent shoots an apparently undocumented migrant near San Diego . The shooting happened in the border town of McAllen, Texas, on Wednesday night. A social justice group decries the trend of Border Patrol shootings toward rock throwers . The migrant died at the scene .