Mexican killed by U.S. agent trying to cross border

A U.S. Border Patrol agent ''drags'' a border road next to one of the tiers of fences along the U.S.-Mexico border in San Diego December 9, 2005.

SAN DIEGO, Calif (Reuters) - A U.S. Border Patrol agent shot dead a Mexican man on the California-Mexico border, U.S. and Mexican authorities said on Wednesday.

Michael Jimenez, a spokesman for the U.S. Border Patrol's San Diego sector, said an agent was involved in a shooting late on Tuesday, but could not give further details.

A newspaper reported the incident began after an agent attempted to arrest three men who crossed illegally into the United States about 1.6 miles west of the San Ysidro Port of entry, south of San Diego, at around 7:30 p.m. local time on Tuesday.

The San Diego Union Tribune newspaper said a second agent arrived to assist. Two of the men fled back into Mexico through an opening in the fence, while the other man resisted arrest.

As he scuffled with the agents, one of the men scrambled up the border fence and pelted the agents with large rocks and a piece of wood studded with nails, striking one of them.

As the man attempted to throw another rock, one of the agents opened fire, hitting him once. He fell off the fence and subsequently died in Mexico, it reported.

Jimenez confirmed a Border Patrol agent had been treated for injuries and released from a local hospital.

In a statement released on Wednesday, Mexico's foreign ministry confirmed the body of a Mexican national had been located in Mexican territory, following a "violent incident" on the border line.

The ministry said the use of firearms to counter attacks with rocks amounted to a disproportionate use of force. It condemned the death, and called for an "exhaustive" investigation into the incident.

The U.S. Customs and Border Protection agency said in a statement released late on Wednesday that a thorough investigation into the shooting death was being conducted by the FBI and San Diego Police Department.

(Reporting by Marty Graham; Additional reporting by Robin Emmott in Mexico; Writing by Tim Gaynor, Editing by Greg McCune)