The eight men found dead on a farm in the Canadian province of Ontario were from Toronto and knew each other, police have said.
Police are not linking the deaths to local gang activity
Police have not released the men's names, and the number of bodies is slowing the autopsy process.
The bodies of the eight men were found in several vehicles in woodland by a farmer on his land at Elgin County.
Bike gangs such as Hell's Angels are known to be active there, but police say no gang involvement is evident.
'Known to each other'
Police launched a murder hunt and say it is possible more bodies will be found. They say all the men were white but have given few other details.
"At this point in time we are confident that the victims were known to each other and from the greater Toronto area," Detective Superintendent Ross Bingley said.
Police have been searching surrounding farmland
It was the largest number of bodies found at one murder scene he could remember in three decades of police service, he told news agency Reuters.
The farm is near the village of Shedden, about 20km (12 miles) from the city of St Thomas, south-west of Toronto.
"It's a pretty isolated area. It doesn't get much traffic, especially after dark," Constable Doug Graham told Reuters news agency.
Police say the bodies were found in three cars and a breakdown truck, parked within 200 metres of each other. But they refused to confirm media speculation that all eight men had suffered gunshot wounds.
'These are bodies'
Officers say the murder probe is at a very early stage, but say the farmer who reported the discovery of the bodies is not considered a suspect.
Russell Steele and his wife Mary, who own the nearby fields, told reporters that the cars were not parked there when they drove past at 2030 on Friday.
They called the police on Saturday when they saw the cars. They were unable to see inside, because a blanket was covering the window.
"We didn't see anybody in them, so we just phoned the cops with the license plate numbers," Mr Steele said.
"The police opened the back and I could see forms," said Mrs Steele.
"I couldn't tell, but immediately in my mind I thought: 'These are bodies'," added her husband.