The Shiawassee County Sheriff's Office is investigating a serious accident involving an ATV.
The accident occurred on Saturday just after Midnight in a wooded area near the intersection of M-52 and Brewer Rd.
A 2010 Polaris Ranger with a driver carrying five passengers was traveling on a two track when it lost control, went off the track, striking multiple trees.
A 29-year-old male from Owosso received serious injuries and was transported to Sparrow Hospital in Lansing.
He is currently listed in critical condition.
The driver of the ATV, a 25-year-old female, was transported to Owosso Memorial Hospital with minor injures.
Alcohol and speed are believed to be a factor in the accident.
The other occupants of the vehicle were not injured.
The Shiawassee County Sheriff's Office was assisted at the scene by Perry Area Ambulance Service.