It happened just before 6 p.m. on the 300 block of Winchester Avenue.
The victim, who has not yet been identified, sustained serious injuries and was flown to a hospital in Fairfax.
Martinsburg City Police and the Martinsburg Fire Department are currently investigating the cause of the accident.
Copyright 2017 Nexstar Broadcasting, Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.