A Waikato man missing since September 2013 may have died in sinister circumstances, say police.
Rick Hayward, 67, was last seen leaving his Hamilton home at about 5pm on Monday 2 September 2013, with the intention of travelling to his family bach at Raglan.
Police initially treated it as a missing person inquiry but now say new information has come to light.
Detective Senior Sergeant Andrew Saunders said police were unable to say what that information was or where it came from.
"We now believe something sinister may have happened to Rick."
Police did believe Mr Hayward may have been a victim of a hit and run.
Mr Saunders said there was no suggestion that someone deliberately ran down Mr Hayward.
"However, the driver might have panicked and disposed of Mr Hayward's body."
Mr Hayward's red Toyota hatchback was parked in Old Mountain Road, near the Karamu track walkway on 2 September and was still there the following day.
The police want information from anyone who used Old Mountain Road to think back to the beginning of spring, almost four years ago.
They wanted to know if anyone saw a vehicle being driven in a dangerous manner, or any sightings of a damaged vehicle.