FOND DU LAC — A Fond du Lac man was listed in serious condition Thursday at Theda Clark Regional Medical Center in Neenah with injuries suffered when his truck veered off Winnebago Drive and overturned.

Authorities are still investigating what happened before the truck driven by John R. Wendels, 59, left the roadway Wednesday afternoon and struck a mailbox, rock, two parked cars and a house before coming to a halt, said Fond du Lac County Sheriff's Department Capt. Dean Will.

The crash occurred about 4:45 p.m. when Wendels was traveling west on Winnebago Drive.

A Flight for Life helicopter transported Wendels to Theda Clark after he was transferred from the accident scene to a landing zone that was set up near Lakeshore School.

A spokesperson at the hospital released his condition.

The house, located at N7043 Winnebago Drive, received minor structural damage, said Sgt. Jeff Bonack.

Wendels was alone in the vehicle. No other injuries were reported as a result of the accident.

Authorities stated that alcohol is not believed to be a factor in the crash.