ALLENTOWN, Pa - Four years ago Monday, a gas explosion rocked the city of Allentown killing several people.
A firefighter who lives close to the scene said, "I looked out my back window and it's like bam the whole place is gone. It's crazy."
North 13th and Allen Streets looked like a war-zone, after a gas explosion rocked the city in 2011.
Five people, ranging in ages from 4 months to 79 years old, were killed in the blast.
Gary Frankenfield knew the elderly couple who died.
He said, "It didn't matter if you came walking down if they see you freezing, they would actually give you a coat or sweater or something to put on."
Lauren Reyes lives across the street from where the explosion happened and said she'll never forget that day.
"I was laying down and when we heard the big boom, the bed jumped a little bit and , we got up right away and I looked out this window and all I saw was big smoke and fire," Reyes said.
Her brother tried to save the other family who was killed.
"You could hear them screaming, but we couldn't help them'" Reyes said.
The Reyes family home was damaged in the explosion.
They rebuilt and decided to stay, but a question still lingers in their minds: How did this happen?
Officials said the blast was caused by a crack in an old UGI cast iron pipe.
A spokesman for the utility company said safety exercises were conducted Monday to mark the four year anniversary of the Allentown explosion.
UGI said it has replaced one third of the old cast iron pipes in the city with more modern materials.
People who live in the area said although UGI is replacing the pipes, the lives lost cannot be replaced and that's why they have a makeshift memorial to honor those who died.
Allentown, PA 18102