It's a decade long mystery - what happened to Ray and Jennie Kehlet in WA's outback.

But cold case investigators are following new leads, revealing three new items of interest have been found.

Three prospectors went on a camping trip to Sandstone, 750 kilometres from Perth, hunting for gold - but only one came home.

Husband and wife Ray and Jennie set off with their friend Graham Milne in 2015 and now, more than a decade on, the trip is still marred by mystery.

Ray Kehlet's body was found 12 metres down an unused mineshaft - a coroner finding he was murdered.

Jennie too - but her body has never been found.

What happened to Ray and Jennie Kehlet is a question still haunting their loved ones.

Ray's brother, Dave Kehlet, has never given up on finding out what happened to his brother a

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