An Anchorage man was arrested on multiple charges after he allegedly hit a person in the back of a head with a hammer.

Gregory Charles Alexis Corpuz, 31, was taken into custody on Friday when police received a call that a person was severely injured near fire station 5 in Spenard. According to charging documents, a witness told officers that a man who goes by the name "G" came up behind the male victim and hit him in the back of the head with a hammer. 

The male was taken to the hospital and rushed into surgery.

"Medical staff reported that [the victim] has a depressed skull fracture and a brain bleed," the charging documents wrote. 

The witness directed officers to a residence on Caroline Drive in the Spenard where the suspect was lying "face down, motionless on the floor,"

"It took of officers some time to get Corpuz to come to, and he appeared to be high on heroin; Corpuz later confirmed he had recently used heroin," charging documents said. 

Officers ended up finding a claw hammer inside his coat. Booking officers later found three credit cards and IDs that were not in Corpuz's name. 

Corpuz was charged with assault in the first-degree and theft in the second-degree.