TUCSON, Ariz. (AP) — A Border Patrol union official says a Mexican law enforcement helicopter fired two shots at U.S. border agents after crossing into Arizona.

The Border Patrol said in a statement that the chopper crossed about 100 yards north into the Arizona desert on Thursday.

Mexican authorities denied shooting at agents and say they were under attack during a mission to find smugglers on the border. No agents were injured.

Border Patrol union local president Art del Cueto (del KWEH’-toh) said four agents were in a marked patrol vehicle when they were shot at.

Republican Arizona House Speaker Andy Tobin said he’s glad nobody was hurt, but said the incident illustrates what he calls “a clear lack of policy and coordination with Mexico” at the border.

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