PELHAM -- The driver of a small motorized "street bike," who lost control of his vehicle at the corner of Marsh Road and Scotland Road about 12:15 a.m. Thursday, is believed to have suffered a very serious head injury, according to police radio and witnesses' reports.

A medflight helicopter using nearby Pelham High School as a landing zone transported the victim to Brigham & Women's Hospital for treatment.

Kaileigh Stelmack, who resides at 6 Scotland Road, told The Sun she was watching TV about 12:30 a.m. when she saw three police cars, an ambulance and fire truck arrive at the accident scene to attend to a male victim who was laying in the roadway with a head injury.

"One of my friends, who drove past the accident scene, told me the guy had blood pouring out of his head, and from his eyes," said Stelmack, relaying her friend's description. "It was scary. It was terrible."

One of the first responders at the scene told Stelmack the crash victim, who was not wearing a helmet, was believed to have lost control of the moped at a curve in the road, she said. There was no indication that a second vehicle was involved.

Pelham police said they will issue a press release on the accident later Thursday morning.

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