A Border Patrol agent fired his weapon at rock-throwing smugglers Tuesday near Cowlic on the Tohono O'odham Nation, authorities said.
No one was injured in the incident, according to a U.S. Customs and Border Protection news release.
Shortly after 4 p.m., Tucson Sector agents in Casa Grande were tracking a group of suspected marijuana smugglers near Cowlic. As the agents neared the group, they were assaulted with rocks, officials said.
Two were taken into custody, and multiple bundles of marijuana were seized, said officials.
The incident is being investigated by the Federal Bureau of Investigation, Customs and Border Protection's Office of Professional Responsibility and the Tohono O'odham Police Department.
No further information was released.
