CAMBRIDGE - A person was found dead in a fire at an apartment building in Cambridge early Tuesday morning.

Flames were shooting out the windows of a first-floor unit of the building on Chester Street when firefighters arrived just before 5 a.m.

Cambridge Fire Chief Tom Cahill said they rescued people from the second and third floors, but when they did a search of the building they found one person dead. That person has not been identified yet.

"It's just a tough way to start the new year," Cahill told reporters.

The chief said there are about 30 units in building and 30-to-40 people were forced out of their homes. There's no word yet on what caused the fire.

"There was such a heavy volume of fire when we did arrive, there's a lot of overhauling to do until we can get to the bottom of where this fire originated and how it started."

One firefighter was taken to the hospital on a stretcher, but Cahill said the injuries are not serious.