Police have appealed for information and dashcam footage as they continue investigating a man's disappearance in southeast Victoria.
Suspicious circumstances are being probed in the disappearance of Morwell resident John Swiety, last seen at Nurran in East Gippsland on March 17.
Police believe Mr Swiety was heading to Goongerah in a white Toyota Hiace van being driven by its owner at about 2am.
Concerns were raised the next day when Mr Swiety's two microchipped terriers were found wandering near a road north of Orbost.
Veterinarians contacted Mr Swiety's sister, who then reported him missing.
Detective Inspector David Dunstan said the van had been found bogged on a dirt track and was being forensically tested for evidence.
The van's owner had been located and was co-operating with police.
"He was travelling with John to the location in Goongerah, he then subsequently left that location leaving John at the location on his own," Det Insp Dunstan told reporters.
"He has been able to tell us that they were travelling up there to visit somebody, we don't know who that person is," he said.
The reason for the meeting was also unknown.
"John has left the location for a period of time. The person who was in the van remained there for several hours. John hadn't returned, and he drove off," Det Insp Dunstan told reporters.
The driver was not currently a suspect and police did not the exact location Mr Swiety left the van, Det Insp Dunstan said.
Mr Swiety was known to police.
"He had some low-level drug priors, this is an avenue obviously we're exploring," he said.
Eastern region detectives had undertaken extensive searches of the local area and found no evidence Mr Swiety had travelled to any other locations.
"The circumstances of his disappearance are suspicious in our opinion ... we believe he has met with foul play," Det Insp Dunstan said.