Authorities have identified an Atlantic, Iowa man whose body was found in a culvert but they are still not sure how he died.

The man is identified as 26-year-old Justin Hoeck.

Hoeck's body was found Monday by an Iowa Department of Transportation crew during a routine inspection of the culvert. Hoeck had last been seen early Saturday morning.

Officials with the Iowa medical examiner's office say Tuesday's autopsy showed that Hoeck didn't suffer any severe injuries and there were no signs he was assaulted.

They say they will wait for the results of toxicology tests before making a final determination.