The victim, who was not identified by Monongahela police, was shot about 9:10 p.m. in Crestview Estates, Washington County 911 said.
Police said they were pursuing a suspect and expected to make a quick arrest. Several police cars convened Saturday night in the 200 block of West Main Street in Monongahela, where they appeared to be confiscating a vehicle.
Police said additional information could be released Sunday.