Queensland police have released CCTV footage of a man believed to have information about the alleged arson and double murder of Ipswich couple Christine and Joe Stephan.
They were found dead after a fire in their Collingwood Park home in Ipswich, south-west of Brisbane on January 23.
Firefighters had to force entry to the house to extinguish the fire, which had taken hold on the lower level.
The bodies of Mr Stephan, 73, and Ms Stephan, 68, were found inside.
Police said post-mortem examination results later revealed their deaths were not caused by the blaze.
Acting Superintendent Steven Blanchfield said anyone from the community who recognised the man in the footage should come forward.
"If that individual sees themselves, we ask them to make themselves known to police," Superintendent Blanchfield said.
"We are also seeking dashcam footage from the area around Zillmere Road, Aspley, and Robinson Road West in Geebung between the hours of 10am and 1pm on Saturday the 22nd of January.
"We're specifically interested in the movements of a black Mercedes Benz around those times. The black Mercedes Benz belongs to the victims and we believe it was stolen from the address where they were located."
Superintendent Blanchfield said police believed the man shown in the CCTV footage may have been driving the car.
He said the pair were subject to "quite a violent assault" before the home was set alight.
"We had a forensic locksmith look at the house for us and give us some information in relation to the security of the house."
A 28-year-old man had previously been arrested over the murder but charges were dropped within hours.
"That individual is no longer a person of interest to our enquiry," Superintendent Blanchfield said.
