A Glenside man allegedly chased a group of bicyclists with his Jeep on Sunday night and intentionally struck one of them from behind, causing serious head injuries that required emergency surgery, authorities said.

Abington Township Police responded to the 2800 block of Meyer Road around 8:30 p.m. for a report of a car colliding with a cyclist. Officers found Colin Cassidy, 24, unconscious and bleeding from his head, police said. Cassidy was rushed to Jefferson Abington Hospital.

Philip Prince, 40, allegedly used his Jeep to pursue Cassidy and three others after he suspected Cassidy had stolen the BMX bike he was riding, prosecutors said. Authorities did not say whether the bike belonged to Prince.

Investigators reviewed video and interviewed witnesses to piece together what led up to the crash.

Prince allegedly followed the group of bikers in his Jeep and got out of the car to confront Cassidy near the intersection of Jefferson Street and Garfield Avenue, less than a mile away from the crash. When the bikers fled, Prince got back in his Jeep and followed them again down the hill of Meyer Avenue, police said.

Cassidy had been riding the bike in the street before he steered onto the sidewalk in the lane opposite Prince's Jeep. At the bottom of the hill, Prince allegedly crossed into the opposing lane and jumped the curb onto the sidewalk to strike the back tire of the bike. Cassidy was thrown about 95 feet from the bike, police said.

After the collision, a juvenile who was part of Cassidy's group entered Prince's Jeep and pressed the ignition button in an effort to prevent Prince from leaving the scene, police said. The juvenile told police he was punched in the face during a scuffle with Prince.

Witnesses told investigators Prince appeared to be driving as fast as 40 mph in pursuit of Cassidy and did not brake before striking the bike, according to charging documents. Some witnesses recorded video of the crash and its aftermath and turned the evidence over to police, authorities said.

Prince's Jeep Compass had a cracked windshield and other front-end damage, police said.

Investigators did not provide any new information about Cassidy's condition on Monday afternoon.

Prince was arrested Monday and charged with attempted murder, aggravated assault by vehicle, homicide by vehicle and related offenses.