The case against Samuel Sithebe, 38, was postponed to December 4 for a formal bail application, Brigadier Neville Malila said.
He was arrested on Monday for allegedly shooting dead a woman, 30, and a man, 35, in their car on November 10 in Geluksdal, on the East Rand.
Malila said Sithebe was found in possession of an illegal firearm, which was stolen during a hijacking in Brakpan in September.
He said the firearm recovered was the same calibre as the one used to commit the murders.
Malila said Sithebe could be possibly linked to other three hijackings and murders in Brakpan in July and August.