WATERTOWN, MASS. (WHDH) - The driver of a flatbed tow truck is in critical condition after officials say he was stabbed multiple times after hitting and killing a woman as she was crossing a street in Watertown Wednesday morning.

Officers responding to the intersection of Galen and Watertown streets about 11:20 a.m. found the woman in the road and the driver suffering from multiple stab wounds, according to Middlesex District Attorney Marian T. Ryan.

The woman, who was said to be in her late 60s, was pronounced dead at the scene. Her name has not been made public.

A man, who witnesses described as the woman’s son, retaliated for her death by attacking the driver and stabbing him at least five times, Ryan said.

The driver, who has not yet been identified, was taken to a Boston hospital with critical injuries.

A witness who saw the woman’s body come out from underneath the tires of the flatbed says the driver repeatedly screamed, “I didn’t see her!” as the man jumped on the truck and stabbed the driver.

“I hear this guy screaming and yelling, ‘you ran over my mother, you ran over my mother,'” Gary Catanese told 7News. “The tow truck driver is yelling back to him, ‘I’m sorry, I’m sorry.'”

Catanese says responding officers had to remove the man from the truck and restrain him before making an arrest. His name has not been released.

State police and Watertown police are investigating.

Just talked to a witness who saw a woman’s body come out from underneath the tires of the flatbed. He said the driver repeatedly screamed, “I didn’t see her!” as another man jumped on the truck and stabbed the driver. #7News pic.twitter.com/okeWY9iuzl — Eric Kane (@EricKaneTV) September 19, 2018

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