There were eight people, including two visitors, in the 1700 Pennsylvania Ave. East duplex when the fire broke out, according to City of Warren Fire Department Lt. Jeremy Rulander.

Four of them were on the first floor. Four were upstairs.

All were able to get out of the home, he said.

Rulander said one resident was transported to Warren General Hospital by Emergycare for smoke inhalation.

Another person drove to the hospital for treatment, he said.

A cat was rescued from the structure and taken to Kinzua Veterinary Clinic for evaluation.

The call went out at 11:53 a.m.

“We arrived to three windows showing with fire,” Rulander said.

Firefighters entered the first floor and found no fire, but discovered that the structure was a duplex, complicating their efforts.

“We found heavy heat and fire on the second and third floors,” he said. “Our biggest issue was void spaces. The fire got into the void spaces above the third floor.”

Firefighters cut holes in the roof at several locations to vent those spaces.

There were no known injuries among firefighters as of 1:30 p.m.

By that time, the active fire had been knocked down and firefighters were addressing hot-spots.

The Warren department was assisted on the scene by North Warren and Pleasant volunteer fire departments. Emergycare and the American Red Cross also responded.

The cause of the fire was not immediately determined.

“It’s under investigation,” City of Warren Fire Chief Dave Krogler said. “We will be calling the fire marshal.”