Correction: Earlier versions of this article gave the wrong gender for the child who was killed.

Story updated at 8:14 a.m. Thursday.

A 3-year-old boy was fatally struck Wednesday night by the family’s automobile after the child’s father thought he parked the vehicle. But the vehicle started moving and ran over the child, Prince George’s County police said.

The incident happened in the 600 block of Audrey Lane in Oxon Hill. The father parked in a parking lot about 7:30 p.m., said Cpl. Larry Johnson, a police spokesman. Two children were in his vehicle.

According to a preliminary investigation, the father left the vehicle and removed a 2-year-old girl from inside, then realized the automobile was “drifting,” Johnson said. The father tried to get behind the wheel and regain control, but before he could, the 3-year-old boy, fell out and was struck.

The child was taken to a hospital, and later pronounced dead, Johnson said.

Police continue to investigate the cause of the accident.

Clarence Williams is the night police reporter for The Washington Post and has spent the better part of 13 years standing next to crime scene tape, riding in police cars or waking officials in the middle of night to gather information about breaking news in and around Washington.