A motorcyclist suffered a serious head injury when he was thrown from his vehicle in Leavenworth, a police spokesman said.

A motorcyclist suffered a serious head injury when he was thrown from his vehicle in Leavenworth, a police spokesman said.

The crash was reported at 6:40 p.m. Saturday in the area of Vilas and Garland streets.

Witnesses reported to the police that the man had been traveling east on Vilas Street at a high rate of speed, according to Maj. Dan Nicodemus, deputy chief of the Leavenworth Police Department.

“The driver lost control of the motorcycle,” Nicodemus said.

The 35-year-old Leavenworth man, who was not wearing a helmet, was thrown from the Suzuki motorcycle.

He was transported to Saint John Hospital. He later was flown by helicopter to another hospital in the Kansas City area. His injuries are considered to be life-threatening, according to Nicodemus.