Four people were injured, one seriously, in four separate weekend motorcycle crashes on Butler County roads, authorities said.

Three of the accidents happened within a 3½-hour period Saturday.

A medical helicopter flew one the cyclists, an unidentified man, to a Pittsburgh hospital with head injuries after he crashed shortly before 3 p.m. Saturday on Route 422 just past the Interstate 79 interchange in Muddy Creek Township.

Emergency crews said the man was unconscious when he was flown to Allegheny General Hospital. His condition was not known.

State police are investigating but a report was not available this morning. Portersville volunteer firefighters assisted.

Less than two hours later, a motorcyclist and car collided on Route 8 near the Freedom Farms Sandwich Shop in Penn Township.

The cyclist, whose name was not available, was injured in the wreck about 3:45 p.m., authorities said. He was taken to Butler Memorial Hospital with apparent minor injuries.

Penn Township police are investigating but a report was not immediately completed. The township’s volunteer fire department was also called.

About 6:15 p.m. Saturday, a cyclist crashed on Victory Road near Spring Valley Park in Jefferson Township. The Penn Township man, believed to be in his 50s, was taken to Butler Memorial Hospital with minor to moderate injuries.

His wife, who was a passenger riding in back, was not hurt,

The man was rounding a bend in the road when he apparently lost control of the bike and hit a guardrail, said Chief Chris Ballina of the Saxonburg Volunteer Fire Company.

He skinned his hand and suffered road rash on his face, authorities said. The man and his wife were both wearing helmets.

State police were called to investigate but an accident report was not immediately available.

Another man was hurt about 4:45 p.m. Sunday when his motorcycle collided with a truck at Route 356 and Harbison Road in Buffalo Township, emergency crews said.

A call to 911 reported the man was lying on the ground. He was taken to an unspecified hospital with unknown injuries.

Buffalo Township police are investigating but they could not be reached for comment this morning. Buffalo Township and Sarver volunteer firefighters assisted at the scene.