Residents in the city's west end awoke to a loud bang on Saturday morning after an explosion ripped through a scrap yard, shattering windows and damaging the facades of nearby buildings and homes.

Cars also caught fire in the immediate area of the Hyde Avenue yard, near Weston and Rogers Roads. The incident occurred at about 9 a.m.

Fire officials said the explosion occurred when a worker punctured a compressed gas tank that he believed was empty. The worker suffered minor injuries.

Two other workers also suffered minor injuries, including a crane operator who had visible cuts to his head.

Residents hundreds of metres away felt the impact. The explosion shattered windows on one home and the windows on one side of an apartment building.

"(It felt like) a bomb. It almost knocked me right out of bed," one resident said.

Those inside a nearby hockey arena also felt the impact.

"All we heard was a boom, and the whole building shook," one man said. "Everybody came running out. We stopped the hockey game."

The explosion was so loud and powerful, some residents in the area phoned the CTV Toronto newsroom asking if there had been an earthquake.

Officials don't yet have a damage estimate from the blast.

Authorities and residents said it was the third time in a year-and-a-half firefighters rushed to the scrap yard for a serious incident.

Large fires broke out at the property in August 2006 and again last August. Both events sent plumes of black smoke into the air and triggered complaints from nearby residents, who said fires there are frequent.

"We have been trying hard to work with residents and do everything right to keep them happy and still operate down here," the owner of the scrap yard, who didn't want to appear on camera, told CTV Toronto on Saturday.

"To have this setback just doesn't sit well with me."

With a report from CTV Toronto's Matet Nebres