Mexican law enforcement chopper crosses into Arizona, fires shots

In this May 13, 2010 photo, Tohono O'odham Nation Police Sgt. Vincent Garcia walks along the new border fence at the U.S.-Mexico border in San Miguel, Ariz.

Ross D. Franklin, AP

TUCSON, Ariz. -- Mexican law enforcement on Thursday crossed into Arizona by helicopter and fired two shots at U.S. border agents, a union spokesman said.

The U.S. Border Patrol said in a statement that a Mexican law enforcement chopper crossed about 100 yards north into the Arizona desert. The helicopter then fired two shots on the Tohono O'Odham Indian Nation, which sits on the border. Shawn Moran, a spokesman for the border patrol union, said the Mexicans fired at agents but that none were hurt.

Sebastián Galván, a spokesman for the Mexican Consulate in Tucson, said the office was gathering information but did not have any details yet.

The area is heavily monitored by U.S. Border Patrol because of frequent illegal smuggling activity involving both drugs and humans, according to CBS affiliate KOLD.

Agent Peter Bidegain, the public information officer for the Border Patrol's Tucson Sector, said there is no information to suggest the shots fired from the helicopter were intentionally aimed at the agents, the station reported.

This incident was not the first one in which the Mexican military has veered across the international boundary.

In January, U.S. border agents confronted two heavily armed Mexican soldiers who crossed 50 yards inside Arizona, the Los Angeles Times reported. A standoff ensued, but nobody was hurt.

In 2011, more than 30 uniformed Mexican soldiers in military vehicles crossed the Rio Grande without authorization in an incident that was believed to be inadvertent.