Photo by Cliff Grassmick

Investigators compare information on the scene at McCall Lake outside Longmont, where a man’s body was discovered submerged Thursday. Investigators ruled out foul play late Thursday, but the official cause of death has not been determined.

A man fishing at McCall Lake, a popular fishing destination northwest of Longmont, discovered the submerged body of a man Thursday morning.

Despite initially investigating the case as a possible homicide, the Boulder County Sheriff’s Office announced late Thursday it doesn’t suspect foul play in the man’s death.

The official cause of death had not been determined at presstime.

Officials have not released the dead man’s name, pending notification of next of kin, but said they believe he was in his 50s.

The man’s body was discovered at 11:44 a.m., but was not pulled out of shallow waters on the east side of the lake until about 4 p.m. An hour later, his red pickup truck, which was parked nearby, was towed away. The tow truck followed behind a sheriff’s vehicle as it left the lake area.

The sheriff’s office said an autopsy will be conducted today and investigators will continue to work on the case.

McCall Lake, a fishing area owned by the city of Longmont in unincorporated Boulder County, was roped off all afternoon as divers with the Longmont Emergency Unit and the Boulder Emergency Squad — clad in red and black dry suits — picked through the dirt and water around the body. Firefighters from the Hygiene Volunteer Fire Department also responded to the scene.

Sheriff’s deputy Sue Cullen said that in an unattended death like the one at the lake, investigators assume the worst and treat it as a possible homicide until they determine otherwise.

Nearby neighbor Eric Ackerman, whose south bedroom window faces the rocky shores where the body was found, said he’s never seen anything like it in the area.

“It’s real quiet out here,” said Ackerman, a retired Longmont police officer. “We never have any problems here.”

Ackerman said he keeps his window open at night and would have heard anything suspicious on the gravel road near the lake.

“I haven’t heard a thing,” he said.

Rob Hunt, a 49-year-old Longmont resident who came to the opposite side of the lake Thursday afternoon to fish for small bass, said he was shocked by the scene.

“It’s amazing,” he said. “Around here, you don’t have that kind of stuff happen. That’s big-city stuff.”

Hunt said the lake is stocked with fish by the Colorado Division of Wildlife and is a huge draw for local anglers. It is located directly west of the Longmont water treatment plant and a few miles east of Lyons, along Colo. 66.