Robbery victim Sherwin Pietersen, 24, died after being struck on the head with a toilet lid at a house in Sherwood on Wednesday.
Police spokeswoman Priscilla Naidu said four men had arrived at the house in Corbin Street looking for the owner, but were told he had gone out.
Two of the suspects were known at the house and had been there the previous night watching movies.
“The group threatened the occupants with a firearm,” Naidu said.
“The hands and legs of the brother of the deceased and his friend were tied.
“The suspects then found Pietersen sleeping. He was struck on the head with the toilet lid.
“They made off with television sets, a laptop computer, cellphones and clothing.”