BEVERLY — A Beverly patrolman is recuperating at home after being struck inside his pickup truck by a 14-wheel dump truck careening down Cabot Street with no driver behind the wheel, according to police and an eyewitness.

The crash happened at noon at the road-repaving work site on lower Cabot Street near the foot of the Veterans Memorial Bridge.

Police said Patrolman Sean Connolly, who was working on a detail with other police officers, was inside his pickup truck to put on rain gear after a heavy thunderstorm arrived, according to Patrolman John McCarthy, department spokesman.

While inside his pickup, Connolly was hit head-on by the driverless dump truck that rolled about two blocks. The end of Cabot Street was blocked off to traffic at the time of the crash.

Bill Beckman, owner of Custom Medicine Pharmacenter at 25 Cabot St., saw the entire accident unfold.

"I was standing at the front door," Beckman said. "I saw the detail officer jump in his pickup because it was monsooning outside — torrential rain."

Beckman said Connolly was in his truck for less than a minute when the dump truck rolled down Cabot Street at a speed he estimated to be about 25 mph, "which was clearly too fast."

But inside the dump truck was something strange.

"There was no driver," Beckman said.

Beckman said the dump truck hit the officer's pickup on the front end on the driver's side, pushing it back about five feet.

Connolly got out of the truck and was walking around after the crash. Connolly, as well as Stephen Saldi of Groveland, who had been driving the dump truck prior to the accident, were taken to Beverly Hospital. A hospital spokesman said both were treated and released.

Beckman said Saldi, who works for White Trucking Co., was injured when he fell trying to get back into his truck. He said the dump truck wouldn't move so the driver got out and tried to push it.

Beckman said had it not been for Connolly's pickup truck, the careening dump truck could have caused a much more serious crash.

The steep incline of the remaining stretch of Cabot Street could have given the dump truck more speed as it crashed into a busy intersection — made worse by the detours off Cabot Street.

The crash remains under investigation.