All are suspected homicides. There is no suggestion the cases are related. 

All could attract a $1 million reward under the new serious crimes rewards matrix approved by the police chief commissioner.

The oldest of the Ballarat cases is that of then 22-year-old Nina Nicholson. 

Ms Nicholson’s body was found on the rear porch of her Suburban Street home in Clunes by her father and brother on September 10, 1991.

The alarm was raised after she did not arrive for a night shift at St John of God Hospital. Based on evidence at the scene, and injuries sustained, police speculate there was a violent struggle before Ms Nicholson was killed.

The second Ballarat case is the murder of 23-year-old Tracey Howard, whose naked body was found in long grass on Clarkes Hill Road, Pootilla, on Monday, November 23, 1998. 

She was last seen at 3.15am on the Sunday after leaving Cheers Nightclub and talking with a man she knew before getting into a taxi.

An autopsy found Ms Howard had been strangled and police believe she may have been killed in her own home before her body was dumped.

The third was 36-year-old Belinda Williams, whose body was found by bushwalkers in bushland off the Mount Buninyong Access Road on July 6, 1999. Ms Williams was last seen by two female friends at her home at 9.30pm with her six-year old daughter. Police believe she was killed in her own home.

“I think it (the $1 million reward) might make a difference. It is human nature,” Ms Williams’ mother, Shirley Macey, said. 

“I’ve always thought someone knows something but the timing hasn’t been right for them. Hopefully, the time might be right now. 

“To have a resolution is very important to us. It would bring peace to our lives.” 

Police also announced a $1 million reward for five other cold cases at the weekend.

The first involved 48-year-old Rosebud woman Helen McMahon, who died from head injuries in February 1985 and whose body was discovered on the Rye back beach.

Bendigo’s Kevin Pearce was shot at a transport depot in Bellevue Road, Golden Square, on the night of April 15, 1985, by an assailant using a .308 hunting rifle. The 45-year-old died in hospital 21 days later.

Debbie Bunworth, 24, was last seen at the Newport Railway Station on September 6, 1985. A 2003 coroner’s inquest found she was a victim of foul play by an unknown assailant.

Geelong West woman Annette Steward was found dead at her Hope Street home on March 18, 1992, by a friend. 

The 29-year-old, who worked at the Winchester Factory in Point Henry, had been visited the previous evening by four male friends.

A post-mortem revealed she had died from strangulation.

Kade Hall, of Croyden, went missing on February 28, 2002, and was found dead in bushland off Mount Dandenong Tourist Road in Kalorama 15 days later with a single gunshot wound to the head.

• Anyone with information is asked to contact Crime Stoppers on 1800 333 000 or make a confidential report at www.crimestoppersvic.com.au