WATERVILLE – Police Thursday afternoon arrested a man who allegedly assaulted another man with a hammer inside a Union Street apartment, drawing a large police response and shutting the street down for an hour.

The incident is being investigated as drug-related, according to police Chief Joseph Massey.

“We suspect it’s over drugs,” Massey said Friday morning.

Zachary S. Larrabee, 31, of 19 College Ave., was charged with aggravated assault, a Class B felony, and criminal threatening with a dangerous weapon, around 3:45 p.m. Thursday and taken to Kennebec County jail in Augusta, according to Massey. Police arrested Larrabee after finding him at his apartment on College Avenue, Massey said.

“The officers did a great job, and the detectives did a great job following up,” Massey said Friday morning.

Larrabee on Thursday reportedly went into Apt. 1 at 11 Union St., a seven-unit apartment building, and struck a man who was visiting there on the head with a hammer. Initially, police believed the man was assaulted with a handgun, but Massey said Friday that it was a hammer and Larrabee also was carrying a Co2 air gun.

“It was quickly resolved and solved and we’ve recovered the weapon and even though it was a Co2 air gun, you’d never know it was not real,” Massey said.

After police got a call at 10:20 a.m. Thursday about the assault, officers, many armed with long rifles, went to Union Street and blocked the street off for about an hour, searching for the attacker, who wasn’t in the building when they arrived. Police had released a radio alert to be on the lookout for a white male wearing a red bandanna and black T-shirt and armed with a hammer and a gun.

Massey said Friday that that once police were able to identify who the attacker was, they started putting out feelers in the community and watched Larrabee’s apartment.

“At some point, he actually called the station and said he knew we were looking for him,” Massey said. “We suspected he had gone into the woods along the riverbank.”

When arrested, Larrabee denied having gone to the Union Street apartment and assaulting the man, Massey said. While police were questioning him, other officers went back to Larrabee’s apartment and found the gun and hammer in a trash bin in the common area of his building, he said.

Residents in the area said police often go to 11 Union St., and Deputy police Chief Bill Bonney said Thursday that officers have responded there nine times since May, once for a report of a man ingesting drugs in the parking lot. However, police at the time did not find him there and were unable to corroborate the claim, according to Bonney.

“There has been some drug activity associated with that address,” he said Thursday. “Whether or not it’s related to the folks in today’s incident is under investigation.”