CHESTER, Pa. (CBS) – Several families were forced out of their homes by a fire in Delaware County.

Neighbors say they are thankful for their close-knit building because the frantic screams and door knocks helped them wake up and get down the fire escape.

Fire raged through the apartment building on West 3rd and Yarnell Streets early Wednesday morning.

Neighbor Daniel Harold was inside at the time.

“It could’ve been worse. I was in a deep sleep, and then I heard people screaming. I wasn’t paying it any mind until I heard ‘get out of the apartment!”’

Firefighters were dispatched around 12:30 a.m.

They arrived just in time to help a family of five as they slowly stepped to safety down the fire escape.

All of the family members were rushed to Crozer Chester’s ER for evaluation.

Chief Joseph Iacono says, “The difficulty is having a building this size, with the limited man power we have on duty. That’s why the second alarm was struck. Crews did an outstanding job.”

By 2:11 a.m., the fire was knocked down and the investigation began.

Officials noted that while no major injuries were reported, working smoke alarms would’ve helped.

“If it had smoke alarms, obviously someone would’ve been alerted sooner. And there’s a very good chance the fire would not have extended as far as it did,” says Chief Iacono.

Police and fire officials believe as many as 13 people may have lived in the apartment.