A woman helping a friend repair a truck Monday night was run over and killed by the driverless vehicle.

At about 8 p.m. Nichole McAlister, 31, was in a parking lot in the 7900 block of North Oracle Road near West Magee Road helping a friend fix his truck.

McAlister “inadvertently shifted the vehicle into reverse, and the vehicle knocked her down and backed over her,” Lt. Kara Riley, spokeswoman for the Oro Valley Police Department, said in a news release. “According to witnesses, the now-driverless vehicle continued in reverse in a circular path, striking the victim two more times.”

McAlister was taken to a local hospital where she was pronounced dead.

The investigation into the incident is ongoing, Riley said.