A 22-year-old Oakton man died after his car collided with a concrete wall Saturday night, Fairfax County police said.

Peter M. Gallagher, of the 11800 block of Wayland Street, was not wearing his seatbelt when his 1999 Mazda Protege drifted off a Vale Road in Oakton Road shortly before 9 p.m. and struck the wall, police said.

The accident occurred near the intersection of Valestra Circle, police said. Investigators have not determined why Gallagher drifted off the roadway, police said. The case is still under investigation.

Anyone with information is asked to contact Crime Solvers by phone at 1-866-411-TIPS/8477.