Calgary police began investigating a suspicious death in the city's northwest Monday after the body of a man was discovered in a grassy area near 16th Avenue.

The body, under a blanket between two trees, was found around noon Monday by people out for a walk just west of the Shouldice Bridge. Police believe it had been there a couple of days.

The man was believed to be between his late 20s and 40s.

Insp. Steve Barlow said the death is being treated as suspicious because there was blood at the scene.

"We found a couple of camps out here, so there's a chance he could have been living out here," Barlow said, referring to some homeless camps in the immediate area.

"At this point, we haven't gone through anything. We don't want to disturb the scene."

Homicide investigators have taken on the case.