Three people were flown by medical helicopters to Pittsburgh hospitals with serious injuries in two separate crashes Saturday less than three hours apart in Center and Donegal townships.

Speed was a possible factor in the first crash about 10 a.m. when a pickup truck rolled over into a wooded area along Route 308 just south of Jamisonville Road in Center Township.

At 12:45 p.m., amotorcyclist lost control of his bike on a notorious curve on Route 68 in Donegal Township, severely injuring a leg.

State police are investigating both crashes. The conditions of the three men injured were not known this morning.

Michael Kuhrt, 21, of Summit Township lost control of his southbound Ford Ranger pickup on Route 308 as the truck rounded a bend in the road.

The pickup crossed into the northbound lane and rolled over before going off the east side of the road, said Chief Mark Lauer of the Unionville Volunteer Fire Department.

Police said the truck flipped onto its roof, throwing Kuhrt and a passenger, Nathan Anthony, 19, of Summit Township, out of the vehicle; neither man was wearing a seat belt.

The truck landed on its wheels and hit a tree in a small wooded area.

Neither man was conscious when first responders got to the crash site. Authorities said Anthony regained consciousness just before he was flown from the scene to Allegheny General Hospital.

Police said Kuhrt was taken by ambulance to Butler Memorial Hospital before being flown to Presbyterian Hospital.

"They probably would have walked away,"Lauer said, "if they had their seat belts on."