BATH — A West Bath man was arrested for aggravated assault following an incident that left another man with a serious head injury, according to police.

Zachary Sewall, 24, was arrested after an officer saw him punch a man in the face outside the Riverside Sports Pub around 1 a.m. Sunday. Police said a large group of people were pushing and shoving each other.

Police said the victim fell to the ground and hit his head on the pavement.  He was taken to Maine Medical Center in Portland.

Police did not release the man’s name, but said he is 27 years old and in the Navy. He is assigned to the USS Spruance, which is scheduled to leave Bath Iron Works this fall.

Sewall was being held at the Two Bridges Regional Jail in lieu of $5,000 cash bail or $10,000 surety.

The incident remains under investigation.