PHILADELPHIA (CBS) – A suspected gas explosion at a South Philadelphia row home sent three people to the hospital Thursday night.

It happened on the 1800 block of South Bancroft Street.

READ MORE: Phillies Superstar Bryce Harper Named National League Player Of The Week After Scorching West Coast Pitching

A PGW spokeswoman says crews responded at about 5:30 p.m. Thursday because of the smell of gas.

Then, less than two hours later, neighbors tell CBS 3 they heard the explosion.

“Like when a bomb goes off, a wall comes down into our backyard. And we didn’t know what it was,” neighbor Joe DeLullo said.

The fire displaced at least three families living on South Bancroft Street just north of Mifflin.

Denise DeLullo’s bookshelf came crashing down after the explosion. She and her husband live directly behind the home where it’s believed the explosion happened just after 7 p.m.

READ MORE: Recent Coastal Storm Uncovers Historic 'Ghost Tracks' On Higbee Beach In Cape May, And It's Not 1st Time

“It looks like an earthquake in our backyard. We can’t even get out the back door. All the rubble from the brick, all the brick is back there,” she said.

The PGW workers were taken to the Hospital of the University of Pennsylvania.  There is no word on their conditions at this time, but their injuries are not life threatening.

Neighbors tell CBS 3 a resident suffered burns to his hands.  There is no word on his condition at this time.

The American Red Cross is on scene helping residents who have been displaced at the True Gospel Church at 16th and Mifflin.

The fire, smoke and water damaged at least three homes in this South Philadelphia neighborhood.

Fire officials and PGW continue to investigate.

MORE NEWS: Police Searching For Dirt Bike Rider Wanted In Hit-And-Run Crash In North Philadelphia