A helicopter controlled by Mexican officials travelled across the border Thursday and fired on U.S. Border Patrol agents, a U.S. official said. Mexico apologized and No one was hurt in the incident, which is under investigation.

“At approximately 5:45 a.m. Thursday morning, a Mexican law enforcement helicopter crossed approximately 100 yards north into Arizona nearly 8 miles southwest of the Village of San Miguel on the Tohono O’odham Indian Nation while on a law enforcement operation near the border,” Peter B. Bidegain III, a spokesman for the United States Border Patrol, said in an email. “Two shots were fired from the helicopter but no injuries or damage to U.S. property were reported. The incident is currently under investigation.”

According to a local news report, the Mexican authorities were on a drug interdiction operation. Border Patrol Tucson Sector union president Art del Cueto told the Tucson NBC affiliate that Mexico has contacted U.S. authorities and apologized for the incident.

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