The family of a schoolgirl murdered in Mackay in 1972 say the arrest of Chris Dawson gives them hope there will be one day be a breakthrough in Queensland’s longest running cold case.

Marilyn Wallman was abducted and murdered while riding her bike to the school bus stop in Eimeo with her brothers, Rex and David.

Her bike was found abandoned and skull fragments were located 40km away.

Marilyn Wallman cold case

Marilyn Wallman cold case

Marilyn Wallman cold case

Marilyn Wallman cold case

Marilyn Wallman cold case

Marilyn Wallman cold case

Just three months ago, the reward for information into her murder was doubled to $500,000 – the largest reward offer in Queensland history.

Rex Wallman told 9News he wanted answers for his parents.

“Mum and Dad definitely need some answers before they get too old,” he said.

“We’re fairly close, we just need those last bits to fill in the holes.”

Marilyn Wallman cold case

Marilyn Wallman cold case

Marilyn Wallman cold case

Marilyn Wallman cold case

Witnesses saw an aqua Holden Commodore drive in and out of Wallman’s Road during the time of her disappearance.

“We do have some information come through at least every week,” Detective Senior Constable Cindy Searle said.

“There have been people speak to us that haven’t previously.

“But we aren’t in a position where we are charging anyone at this time.”

Anyone with information should contact Crime Stoppers on 1800 333 000.

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