The border patrol agent, whose name has not been released, shot and killed 15-year-old Sergio Adrian Hernandez Huereca after a group of suspected illegal migrants threw rocks at the agents at an international bridge near downtown El Paso, Texas on Monday evening, according to the FBI, the lead agency investigating the shooting. The agent was 12 yards from the border, on the U.S. side. The victim was on Mexican soil.
The killing was condemned in Mexico as an abuse of power. Calderon said in a statement Tuesday that his government "will use all resources available to protect the rights of Mexican migrants."
This is the second time in two weeks a Mexican person has been killed by a U.S. border patrol agent.
Mexican migrant Anastacio Hernandez, 32, died after a Customs and Border Protection officer shocked him with a stun gun at the San Ysidro border crossing that separates San Diego and Tijuana, Mexico. Last week the San Diego medical examiner's office ruled that death a homicide.
U.S. Customs and Border Protection spokesman Doug Mosier said border agents are trained to use force when their lives or the life of a third party is threatened. "A rock is considered a lethal weapon," he said. "Agents have been seriously injured by rocks. It's a problem all along the border."
In 2007, a U.S. Border Patrol agent was tried for second-degree murder in the shooting death of an illegal Mexican migrant just north of the Mexican border near Naco, Ariz. The agent claimed the migrant was threatening him with a rock. The case ended as a mistrial.
The Mexican Foreign Ministry on Tuesday condemned the latest death, saying that "the use of firearms to repel attacks with stones represents disproportionate use of force, particularly coming from authorities who have received specialized training."
Chihuahua State officials released a statement Tuesday demanding a full investigation into the death of the boy, whose body was found under the Paso Del Norte border bridge -- an old railway bridge known as "el puente negro" -- in Ciudad Juarez, Mexico. He was shot once near the eye, and authorities found one .40-caliber casing near the body, said Arturo Sandoval, a spokesman for the Chihuahua Attorney General's office.
"I was near the flagstaff on the bridge waiting for my wife and suddenly I saw the boys enter from the American side; a migration agent pursued them and they went back. An official on a bicycle went toward the Mexican side and started shooting at the boys," a witness told Ciudad Juarez newspaper El Diario. Afterward, two unarmed men were taken into custody.
According to an FBI news release Tuesday, the border agent warned the group to stop throwing rocks and retreat, but when the order went unheeded, the agent took out his weapon and fired several shots. While the lawfulness of the shooting will be investigated, it will likely be exonerated, said FBI spokeswoman Andrea Simmons.
"If you are trying to detain someone and they are throwing rocks and not listening, I suspect that's going to be within their deadly force policy," she said.
The boy's sister, Rosario Hernandez, 25, said that her brother was playing with several friends near the border but was not attempting to illegally migrate into the U.S.
"He never planned to cross the border," she said of her brother, who aspired to be a police officer and whose body currently lies in a bedroom in the family's house. She learned of the shooting from one of her brother's friends who witnessed it and went to the bridge to identify the body.
"My mother is inconsolable," she said.
A group of protesters at the site of the shooting, including the victim's mother, a Juarez city employee, were dispersed by a U.S. official's gunfire, Hernandez said, adding that her family is in the process of filing a claim with the state attorney's office.
"All my family wants is that the guilty pay for what was done to my brother."
The killing comes at a time immigration is a hot-button issue in the U.S. During a state visit to the White House in May, Calderon reiterated his "firm condemnation" of the Arizona law that gives the police broad power to detain anyone suspected of being in the country illegally.
Ten days later, Obama said he would dispatch 1,200 additional National Guard troops to the border and spend $500 million to step up border patrols, winning the approval of the Mexican government.