The city transit union president says an Edmonton bus driver injured in a violent attack Friday was punched in the eye, cut in the neck and bitten.

The Edmonton Transit System driver was treated in hospital and released following the Friday afternoon incident, Mark Tetterington, president of the Amalgamated Transit Union Local 569, said Monday.

The driver was assaulted by a man on his bus in the Castle Downs area around 2 p.m. The suspect ran off, and no passengers were injured.

"I talked to him just after he was released from hospital, he was transferred to the Royal Alex," Tetterington said of the driver.

"He was apparently punched in the eye, he received some stitches. And I think he was also bitten."

Tetterington said the driver, who has more than 10 years' experience, was attacked over an expired bus transfer.

During the altercation, the suspect allegedly broke the Plexiglas door that separates the driver from passengers.

"The door compartment and the driver's door was ripped off," Tetterington said. "And as he ripped it off, it broke in half. And I guess a jagged edge, he held it up and hit him with it.

"Now I'm not sure the chain of events, whether it was after he got punched or bitten. But he hit him with it, and it cut his facial area, down towards his neck. And he had to get 10 to 15 stitches, apparently."

Tetterington said during training, Edmonton transit drivers are told not to engage in fare disputes.

"We tell them not to worry about fare disputes. It's not worth getting hit, or spit on over a fare dispute."

ETS has launched a safety investigation, and is offering the driver counselling.

Edmonton police are reviewing surveillance footage from ETS in hopes of identifying a suspect.