Police in Maryland say they're investigating an arrest during which an officer punched a 19-year-old outside a bar.

Bystander video posted on YouTube shows three officers struggling with 19-year-old Zachary Blumenstein of Chevy Chase early Saturday. One punches him.

Baltimore County police Chief Jim Johnson said Sunday in a statement that he'll review the incident, but his initial reaction was that other techniques "could have been more effective."

The statement says an officer saw Blumenstein push a man into the road. Police say the officer told Blumstein he was under arrest, but he resisted even after an officer used pepper spray.

Police say Blumenstein was charged with resisting arrest, disorderly conduct and other offenses, and then released.

A message left at a number listed for Blumenstein's address wasn't immediately returned.

The name of the officer who punched Blumenstein hasn't been released.