Border Patrol agents in Starr County were shot at on Wednesday while responding to a report of suspected migrants in the area, according to U.S. Customs and Border Protection.

Agents were near the city of Fronton when the shooting occurred.

“Responding agents reported shots fired from Mexico,” CBP said in a statement. “Texas Department of Public Safety, Starr County Sheriff’s Office and additional agents responded to the location."

The Federal Bureau of Investigation, the Department of Homeland Security Office of the Inspector General and Custom and Border Protection’s Office of Professional Responsibility were notified of the incident.

No further details were provided.