Five months after he was found stabbed to death on a riverbank, detectives say they're still not sure whether high flying Durham solicitor Peter Maine was murdered or took his own life.
And now after months of exhaustive inquiries they're trying to trace three mystery figures who could hold the answers.
Watch Gregg Easteal's report here.
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Veterans, cadets, dignitaries and serving Northumberland Fusiliers have paid tribute to those killed at the Battle of the Somme
Clear spells. Showers. Brisk winds. Sunday looks like the better day
Two men whose grandfathers fought in the Tyneside Irish battalion and died together on the Somme have returned to visit their graves.