WORCESTER, Mass. -- Five Worcester firefighters were injured Thursday afternoon while battling a four-alarm fire in a six-story high-rise apartment complex in the New City Square area of the city. Several residents had to be helped through upper-story windows to escape the blaze.

Some residents were evacuated using fire truck ladders after the fire broke out the Griggs Building rooming house at 167 Pleasant St., about 2:30 p.m.

"Ladder 2, the first ladder truck in the front of the building made several heroic rescues of people trapped in their windows who could not make it out from the inside," said Worcester Fire District Chief Frank DiLiddo.

Heavy smoke and flames were seen pouring from the building as firefighters on ladder trucks worked to squelch the blaze with water hoses.

"It was such an intense firestorm when we were inside, we got some firefighters that have second-degree burns. We had some heavy, heavy volume of fire right at the initial stages of this fire," DiLiddo said.

There was no immediate word on a cause of the fire in the brick structure.

"I was trying to get my cats together because they were like, 'Leave! Leave!' because the fire alarms went off. I thought it was a drill, but this time it was really going on, so I was trying to get all four cats in a bag and get out, you know?" resident Shannon Blash said.

A woman at the Pleasant Street Baptist Church next door said the flames had spread to the church steeple there by 3:30 p.m.

The building's roof had partially collapsed by 5 p.m.