A 24-year-old man was allegedly attacked and bludgeoned to death with a cement block during a scuffle in Worli area of the city, police said on Saturday.
The incident took place on the eighth floor of a building at Dr Annie Besant Road in Worli on Thursday morning, an official said.
The victim Deepak Shashlal Yadav was involved in a scuffle with the 18-year-old accused, over some minor issue, he said.
The accused hit him with a wooden plank and then proceeded to attack him with a cement block, killing him on the spot, the official said. A case of murder under relevant provisions of the Indian Penal Code was registered against the accused, who has been arrested, he added.