At least three people died after a dump truck slammed into a group of motorcycles at 27th Drive and Carefree Highway in north Phoenix.

Video from motorcycle crash scene | Photos

Eight motorcycles carrying at least nine people were stopped at a stop light when the large truck apparently hit them from behind, Phoenix police spokesman Luis Samudio said. Three bodies were pinned under the truck.

Tania Krukoff, an employee at a nearby Walgreen's, said she was returning from a nearby gas station when she came upon the accident and talked to the driver of the truck.

"He was in shock," Krukoff said. "He (said) he wasn't paying attention, just shuffling with his paperwork."

Six people more were taken to local hospitals, one of them being a Phoenix fire captain, Samudio said.

The firefighter, Ernie Lizarraga, is a 22-year veteran of the department, officials said. He was taken into surgery.

Lizarraga is a member of a motorcycle club called Phoenix-M-C-Kruzers. Authorities have not yet confirmed whether the riders hurt Thursday were with the club; however, an invitation for Thursday's ride posted by Lizarraga on the Web site, meetup.com, told riders they would go to Carefree "and off to Bartlett Lake."

"I just WANNA RIDE," he told members of the Web group.

After the accident the Blue Sky Sanitation truck was smoking, and popping could be heard before it burst into flames. Witnesses saved at least two people who were near the truck when it caught fire by pulling them to safety. Motorcycles were said to be spread out 20 to 30 yards behind the truck.

A medical helicopter landed at least twice to transfer victims to the hospital.

After the truck hit the motorcycles, the truck burst into flames and hit a sports-utility vehicle, a pickup and a sedan. No one from any of those vehicles was injured, Daisy Mountain Fire Department spokesman Phil Dyer said.

The driver of the truck was not injured. Officials said there were no initial signs of impairment. The Carefree Highway was expected to be closed for several hours.

Lynn McDowell, also a Walgreen's employee, ran out with other employees to help.

"I grabbed all the water I could and took blankets because there were bodies everywhere," McDowell said. "It was horrible."

The truck driver, she said, "got out of the truck and tried to help the people under the truck.''

"The flames were so high you couldn't get close," she reported. She and others took fire extinguishers from Walgreen's to try to extinguish the flames.

Jarrod Cook owns Ketzal Mexican Grill near the scene. He said he has closed his shop for the day because of the accident.

All six that was transported are in critical condition. At least 50 firefighters and two ladder crews responded to the scene.

Transportation officials said the road would reopen by 7 a.m. Friday.