A fire in Allentown, Pennsylvania, Thursday night left several injured and displaced at least five families. 

The fire broke out around 4:30 p.m. Thursday on the 700 block of Cedar Street, according to the Allentown Fire Department. 

According to the affidavit of probable cause, the fire then spread to six additional rowhomes, and dozens of firefighters responded to the blaze. The fire displaced 30 people, Allentown fire officials said in an update Friday.

Allentown Fire Captain Mike Pychinka says freezing temperatures made treating the area difficult. 

"You have to watch for slip hazards, and it's not easy when guys are up on the roof working and it's cold like this and everything is freezing up," Pychinka said.

Seven people — including four firefighters — were taken to the hospital. The firefighters are expected to be OK and one of the civilians was listed in critical condition.

Chopper 3 was overhead Thursday around 6:30 p.m.

Brian Onofre lives down the street and went to check on a friend. 

"As I went down there, I could feel the heat," Onofre said. "I had to cover my face because of the smoke."

Jariel Lopez lives across the street and worked with his family to help others who had to evacuate.

"We tried to do our best to start giving hoodies out," Lopez said. "Kids were out with no socks. We tried to get them socks."

The cause of the fire is under investigation.