Prime suspect in Frankston murders says he's innocent as cops announce record rewards

The prime suspect in the infamous Tynong North and Frankston murders has declared his innocence on the same day police offered a $6 million reward for information leading to an arrest.

Elderly man Harold Janman broke a decades-long silence to tell Seven News he's not the serial killer who took the lives of six women.

The taskforce set up to investigate the murders and the original homicide investigation have certainly indicated that the six cases are linked.

On Saturday, the man who's been the prime suspect since the 1980s again protested his innocence.

PICTURED: Top: (L) Allison Rooke, Bertha Miller, and Catherine Headland. Bottom: (L) Ann-Marie Sargent, Narumol Stephenson and Joy Summers. Source: Victoria Police.

"I never ever didn't, I didn't know those people. I never saw those people and I never thought of murdering," Janman said.

"I didn't have I was too busy working long hours."

Janman is just one of almost 2000 people interviewed in relation to the Tynong North murders.

But the 85-year-old could soon find himself being questioned again.

On Saturday, police announced they're starting the investigation from scratch, with no suspect ruled out.

Harold Janman is the prime suspect in the case. Source: 7 News

Police, joined by the victim's families, offered the $6 million reward for information that could find one man responsible for all six murders.

"This is the largest amount of money ever been offered in regard to a single investigation," Detective Inspector Mark Hughes said.

The first body was found in 1980 on McCelland Drive in Frankston and was identified as 59-year-old Allison Rooke.

Months later, teenagers Catherine Headland and Ann-marie Sargent as well as 73-year-old Bertha Miller were found dumped near a quarry in Tynong North.

The following year, 55-year-old Joy Carmel Summers was found in scrubland at Frankston North and then two years later, another body at Tynong North was uncovered, identified as Narumol Stephens.

"The victims were all either on the way to use public transport or were on foot," Det. Insp. Hughes said.

Janman has admitted to offering women lifts in Frankston around the time of the murders and has failed two lie detector tests.

On Saturday, the ageing man echoed a sentiment shared by the victims grieving families.

"I hope they find the true person that's responsible," he said.

Peter Sargent said he knows they all want the same thing.

"We want that vital bit of information be given to the police to help solve the case," he said.

Police are hoping the passage of time can help them solve these cases.

People who may have been unwilling or too frightened to come forward could now, years later, change their mind.

"We progress a lot of these investigations through relationships changing and if someone has assisted or knows something about this we are obviously appealing for them to come forward," Det. Ins. Hughes said.