CHICAGO (CBS) — Chaos erupted at a Northwest Side hospital overnight, when dozens of firefighters rushed to extinguish an extra-alarm fire at Presence Resurrection Medical Center.

Two firefighters suffered minor injuries putting out the blaze, which started around 9:30 p.m. near the kitchen area on the second floor, and quickly spread to the hospital chapel.

Firefighters raised two extra alarms to bring in extra crews to fight the fire. In all, about 80 fire companies responded to the blaze.

The location of the fire presented the Fire Department with some serious challenges.

“Very high up there; you’re looking at 40 feet in height, and so we had to crawl up in there to get to the seat of the fire, to make sure we had it out,” Fire Commissioner Jose Santiago said. “That was the most difficult thing, was the small catwalk, so only a few people can walk in there. That’s the most dangerous part, because you don’t know what might happen.”

Forty patients were evacuated from their rooms to another part of the hospital.

A total of about 230 patients were in the hospital at the time, but no patients or hospital employees were injured in the fire, although two firefighters were taken to Advocate Lutheran General Hospital in Park Ridge for minor injuries. They were listed in good condition.

The fire was struck out about three hours after it started, but by then, the hospital had sustained heavy damage, especially in the chapel area.

“The cathedral’s pretty large. It’s a large cathedral, that’s why we had so much smoke in there. We had to move patients to safety. There’s a lot of water damage right now, and the hospital will make some decisions about what they’re going to do next,” Santiago said.

A cleanup effort was underway Friday morning.

“We have a lot of water in the hospital, and we’re trying to move that water out of the way, so they can get everything back in order,” Santiago said.

The cause of the fire was under investigation.