Several explosions triggered a multi-alarm fire Wednesday afternoon at a gas company in Collingdale, Delaware County prompting a four-block evacuation. Authorities say one person is hospitalized in critical condition and two others were also taken to the hospital with non-life threatening injuries. A firefighter suffering from heat exhaustion was treated at the scene.

KYW’s Pat Loeb reports fire officials say a series of explosions rocked Scully’s Welding at about 12:45 and touched off a fire in two propane tanks that together held some 14,000 gallons of propane.

Firefighters used water cannons to cool the tanks and extinguish the blaze, a process that took 5 and a half hours.

Residents in a 3000 foot radius were evacuated for 6 and a half hours, until the fire was completely out and foam was spread to prevent flare-ups.

The county criminal investigation division is trying to determine the cause but officials say that doesn’t mean the fire is suspicious, just that it was really really huge.

KYW’s John McDevitt reports hundreds of homes and business were evacuated due to the explosion.

Police officers went door to door telling residents to leave their homes. Area businesses were evacuated too. Victoria Matteo who is several months pregnant was on business in a nearby restaurant/bar.

“We didn’t know what was going on and there was explosion after explosion.

McDevitt: What went through your head?

“Just that I was going to be okay and my baby wasn’t going to come out. I only have six weeks left.”

Many residents went to evacuation centers, some very concerned about when they would be reunited with their medications and the pets they left behind.