STOCKTON (CBS13) — A Stockton police officer patrolling on a motorcycle has been flown to the hospital after a crash sent him flying into a windshield.

Police said the circumstances that led to the crash is still under investigation.

An employee at a nearby business, who did not want to be on camera, was driving into work when she noticed a Stockton Police officer on a motorcycle. She was behind the officer just as he was about to make a stop.

“The opposing vehicle turned left, and that is when they collided together and the officer flew onto the windshield, and that is when he fell to the side and that’s when the motorcycle literally skid from like mid-intersection all the way to the light,” she said.

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The accident happened just as police were participating in a special law enforcement operation focused on distracted driving.

“It was a bang. It sounded like crunching metal, like enough to look. It got my attention,” said Donald Dew, who was waiting on an Uber driver when the crash happened.

Investigators say the driver involved in the crash remained on scene. He is cooperating with police. As for the officer, we’ve learned he’s a veteran of the Stockton Police Department assigned to the traffic division.

“That’s very unfortunate, nobody should ever go to work and come back differently than how they were so that is definitely sad for both parties, for the kid who is probably shaken up by now and that officer. My prayers are with everyone right now,” said Dew.

Stockton police say the officer is being treated at the UC Davis Medical Center. He remains in serious condition.

The department is now conducting a thorough investigation.

“We’re still trying to figure out what exactly the details the lead up to this collision,” said Joe Silva, Stockton Police Department.

Police said the officer and his family are appreciative of all the thoughts and prayers.