Police believe stolen war medals and a royal blue car may hold the key to solving the murder of a great-grandfather on a rural property at Springbank, near Ballarat, Victoria last month.

Kenneth Handford, 90, was found dead in his home on Barkstead Road on his birthday, September 15.

He was discovered in his bedroom when neighbours went to check on him when birthday calls went unanswered.

Detective Senior Sergeant Stuart Bailey from the Victoria Police homicide squad said he believed his death was the result of a bungled burglary because it was well known that Mr Handford carried a lot of cash.

"Previously he used to cash checks for people. He was a kind and generous man and he hadn't done that for a couple years but that's what he used to do and it was well known in the community that he used to carry cash," Senior Sergeant Bailey said.

"Now I'd say they targeted Mr Handford for that reason and it's been opportunistic that they found the medals there and they took them."

Tracing medals may lead to killer

It was believed Mr Handford may have tried to fight off his attackers in an attempt to protect his belongings including his World War II medals, which were also stolen.

He served in the Royal Australian Airforce between 1943 and 1946.

Police released a photo of a replica of the stolen medals which include the 1939-1945 Star, the Pacific Star, the 1939-1945 War Medal and the Australian Service Medal, 1930-1945 and a return from service badge.

"I certainly believe if we can trace the medals we'll trace the murderers in this crime," Senior Sergeant Bailey said.

A royal blue 2005 Nissan Pulsar or Ford Focus hatch was seen in the area on the afternoon of September 13.

Detective Senior Sergeant Bailey said the car was not owned by locals and police were trying to identify the driver.

"We'd like to speak to the person who owns that vehicle to establish why they were in the area and establish could they be a witness to the crime or could they in fact be the offenders involved in this horrific crime," he said.

The war medals may have been "innocently purchased" police said, and anyone with information is urged to contact Crime Stoppers.

Mr Handford's son Peter said his father seldom spoke about his war service and only recently showed his war medals to a great-grandson.

He thinks he may know who is responsible for his father's death but said the investigation had to be left to take its course.

Peter Handford said the his father's house was packed up and Mr Handford was going to move in with him and there was plenty of other expensive goods that were left behind.

"We believe the money and the medals are the only things missing," he said.

His brother Ron, 81, said Mr Handford was a "hard worker" who would help people with money or if they were sick saying his brother "would've put up a fight."