Cobb County police are investigating a wreck Saturday afternoon that left a 55-year-old man dead.

The wreck happened about 12:45 p.m. on Powder Springs Road north of Pamela Circle.

Cobb police spokesman Mike Bowman said a 1998 Nissan Maxima left the roadway, hitting a mailbox, a small concrete wall and a tree before overturning.

The Maxima driver, Steven G. Townsend of Powder Springs, was taken to Wellstar Kennestone Hospital, where he was pronounced dead.

“Investigators believe that Mr. Townsend may have suffered a medical condition prior to the collision,” Bowman said.

No other cars were involved, and there were no other injuries.