The shooting of Sergio Adrian Hernandez Guereca of Juarez on the Mexican side of the border across from El Paso, Texas, occurred Monday when a group of individuals threw rocks at U.S. border agents taking two men into custody for illegally crossing the border into the United States, U.S. authorities said.
Mexican President Felipe Calderon condemned the shooting and the country's secretary of state called it a "disproportionate use of force," the El Paso Times reported Tuesday
The U.S. State Department said in a statement acknowledged that an agent had fired his weapon killing "one of the suspects" allegedly hurling rocks.
"We regret the loss of life," the statement said.
Mexico's Chihuahua state police said the youth was shot once in the head.
U.S. authorities said the agent, whose name wasn't released, was defending himself. The officer was placed on administrative leave.
The U.S. Federal Bureau of Investigation and Mexican authorities were investigating.
The boy's father, Jesus Hernandez, had not been involved in the rock-throwing or illegal border-crossing incident.
"He wasn't a troublemaker. He didn't have vices," Hernandez told the Times.
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