UPDATE 3:50PM ET: A city spokesperson from teenage victim Sergio Adrian Hernandez Huereca’s hometown of Juarez condemned the shooting, saying that Hernandez was with other friends playing around the international Paso del Norte bridge. CNN reports that Hernandez, who was not armed, was shot in the head. T.J. Bonner, the president of the union representing Border Patrol agents has said that rock-throwing at Border Patrol officers, which Hernandez and his friends have been accused of, is a common occurrence at the border. "It is a deadly force encounter," Bonner told the Houston Chronicle. "One that justifies the use of deadly force." ………………………… UPDATE 1:27PM ET: Details are emerging about the cross-border exchange that led to yesterday’s shooting, which happened at 7:30pm. The El Paso station KVIA reports that witnesses say a group of people from the Mexican side of the border started throwing rocks across the border after a Border Patrol agent tried to stop a teenager who was trying to enter the United States. Border Patrol maintains that their agent started shooting in self defense. The FBI is now investigating the case. ………………………… A U.S. Border Patrol agent shot and killed a 14-year-old boy named Sergio Adrian Hernandez Huereca last night an a bridge near downtown El Paso, said Mexican officials. This morning, the AP reported that Chihuahua State officials demanded an investigation into the boy’s death. U.S. Customs and Border Protection confirmed that one person was shot on the Mexican side of the the border, where El Paso, Texas and the Mexican city of Juarez meet. Last week, family and mourners gathered on both sides of the San Ysidro and Tijuana border to protest the death of Anastacio Hernandez, a 32-year-old man who died after a Border Patrol officer shot him with a stun gun on May 26. Hernandez’s death was ruled a homicide. Photo: Border in El Paso, TX, Getty Images/Chip Somodevilla