By CBS3 Staff

PHILADELPHIA (CBS) – Philadelphia firefighters made dramatic rescues when a house in Bridesburg went up in flames overnight. Now, the fire marshal is taking a close look at how that fire started.

Police say the fire hasn’t officially been ruled an arson but they do have strong leads they’re following up on.

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Three people were injured and taken to the hospital for treatment, and that includes two children. They were rescued by firefighters from a second-story window.

2 Children, Woman Rescued From Burning Rowhome In Bridesburg; Fire Investigated As Possible Arson

When fire crews arrived, they were hanging out of a side window waving to first responders for help.

Eyewitness News was at the scene as firefighters and EMS rushed to help. The kids were seen getting oxygen and a woman was wheeled away to an ambulance.

First responders arrived on the 2200 block of Kennedy Street around 2 a.m. Wednesday. The back of the two-story rowhome was already engulfed in flames.

The deputy fire chief says there was an aggressive interior attack to get the flames under control as quickly as possible.

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“The rear of the property is wood frame and the hazard is collapsing in the rear because that’s where the majority of the fire was,” Philadelphia Fire Deputy Chief Vincent Mulray said.

Fire crews had to make three rescues at the home where the fire started. A 56-year-old woman was rescued by firefighters. She was taken to the hospital in critical but stable condition.

Her two grandkids, a boy and a girl, 10 and 13 years old, had to be rescued from the house by firefighters with ladders. They are at St. Christopher’s Hospital in stable condition and are being treated for smoke inhalation.

Meantime, neighbors had to rush to get their families to safety. One man had just come home from walking his dog when he noticed the flames at his next-door neighbor’s home. He knew he had to get his sister out of his house.

“I tried to get in my house. Got in my house. My sister was sleeping,” neighbor Leonard Delvalle said. “She didn’t know the house was on fire next door. I ran upstairs to the bedroom. My whole back room was on fire. The windows were yellow, bright yellow. There were flames coming through the window, breaking through the window. The whole room was on fire. Thank God she got out safe.”

The fire marshal’s office is now investigating the cause of the fire but police tell Eyewitness News it is being investigated as a possible arson.

Meantime, one neighboring home has some damage too. Three people were displaced and are being helped by the Red Cross.

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CBS3’s Jan Carabeo and Alecia Reid contributed to this report.