Homicide Squad detectives are investigating a fatal assault in Werribee on Monday night last week (Dec. 2).
A man was located with life-threatening injuries inside a Everwin Drive property about 7.10pm.
He was transported to hospital where he died several hours later.
A 55-year-old Werribee man was arrested at the scene and was expected to be interviewed.
Detectives are making enquiries to determine the circumstances surrounding the incident and investigations remain ongoing.