Investigators know little about a man whose badly decomposed body was pulled from the Mississippi River in Sauget about 10 a.m. Friday, according to St. Clair County Coroner Rick Stone.

Authorities are uncertain who the man is or how he ended up in the river. An autopsy did not reveal any cause of death or obvious signs of injury or foul play such as bullet holes or broken bones, Deputy Coroner Dan Haskenhoff said.

"We got no idea, no leads," Haskenhoff said.

The man had been in the water for about a week when a Kinder Morgan crane operator spotted his body floating in a logjam near a barge.

The white man had dark hair and was about 25 to 30 years old, 6 feet to 6 feet 4 inches tall and about 180 pounds, Sauget Police Detective Sgt. Vito Parise said.

He had no tattoos or facial hair. He was wearing a gray T-shirt that showed a man with a bicycle jumping over a fence.

Haskenhoff was unaware of any missing person reports that could be related to the man. He has been calling authorities across the St. Louis metro area searching for leads in the case.

The man was retrieved from the river at 2 Monsanto Ave. by the Sauget police and fire departments with assistance from the St. Louis Fire Department.

Sauget Police can be reached at 332-6500.