A Winnipeg Transit driver was attacked but not seriously hurt when a man threw a chunk of concrete at his head.

Police believe the attack at a bus stop near Ellice Avenue and Simcoe Street in the West End on the afternoon of May 24 was prompted by an earlier incident around 1 p.m. near St. Vital Shopping Centre.

The man got on the bus but refused to pay and got into an argument with the driver. The driver continued along his route as the argument carried on before the man finally got off in the downtown area.

A short time later, the driver saw the man waiting at the Ellice Avenue stop. The bus pulled over to let other passengers board and exit, which is when the man threw the concrete then ran away.

The driver did not suffer serious injuries, police said.

The man who attacked the driver is described as 20-30 years old with braided black hair. He is about 5-10" and 145 pounds, police said.​

John Callahan, president of the local branch of the Amalgamated Transit Union, said the driver is back at work now.

​The attack is the latest in a string of assaults on transit drivers, one of which killed Irvine Jubal Fraser, 58, in February.

Fraser was stabbed to death at the final stop of his shift by a passenger. Brian Kyle Thomas, 22, has been charged with second-degree murder.

The high-profile incident sparked rallies by transit employees who called for the city and province to take steps to make buses safer for drivers and the public.

"I don't know what's going on out there, but, I mean, every day it's something," Callahan said. "These are operators looking after people, trying to do the best they can and make sure that they're safe and everything else.

"I don't understand why they are being targeted when, like I say, they're just trying to perform a crucial service."

Callahan said several operators have left their jobs recently because of safety concerns.

"That's the reality now, unfortunately," he said.

The city is considering a package of transit safety improvements that include a driver-shield pilot project, a video-surveillance system expansion and a small private security force.

Callahan said improving safety will take time and resources.

"There's a lot of positive things that are happening, but obviously it's not quickly enough," he said.