Chicago Fire Department officials now say 17 firefighters were injured in a blaze that left two dead.

The city's fire commissioner, Robert Hoff, says every firefighter at the scene on Wednesday "did the best they could to save their brothers."

Hoff and firefighter's union chief Tom Ryan spoke at an emotional news conference hours after the blaze.

Ryan says "no matter how much experience you have on the job, a morning like this still takes you by surprise." He says victims' families can take solace in knowing the men are heroes.

The men who died were among four firefighters buried in debris when the South Side building's roof and one wall collapsed.