A White Mountain Apache Police officer has been arrested in connection to a fatal hit-and-run accident in northeastern Arizona, authorities said Monday.

Officer Josh Anderson was arrested Friday evening by fellow tribal officers at his home in Whitewater on the Fort Apache reservation following last week’s crash, according to the Navajo County Sheriffs office, which released the information on behalf of the White Mountain Apache Police. Anderson resigned immediately after his arrest.

The sheriffs office said Iris Billy was walking when he was struck by a vehicle that fled the scene early Thursday on state Route 73. The statement did not provide Billy’s age or other details.

Tribal police soon determined that Anderson’s patrol car had damage consistent with a collision with a pedestrian. He was booked into the White Apache Adult Detention. He could be charged with death caused by a vehicle and leaving the scene of a fatality collision, according to officials.

It was unknown whether Anderson had an attorney or anyone else who could speak for him. The tribal police department referred questions about his legal representation to the sheriff’s office, which did not immediately return an email and a phone call.

The White Mountain Apache Police Department turned the case over to the FBI, which will investigate. The U.S. Attorney’s Office will later review the findings and decide on any formal charges.