The cause of the blast was unclear. Two neighboring homes were severely damaged and were condemned.
Cesar Coto, 52, and Miguel Irizarry, 41, were conscious when they were extricated from the leveled home and taken to a hospital, Fire Chief Robert Scheirer said. The extent of their injuries was not clear.
Scheirer said he felt the blast in his office about a mile away and thought something in his building had blown up.
Broken glass littered a lawn across the street from the destroyed house. Debris was scattered about, in addition to the tree-bound wheelchair.
A neighbor, Bob Walko, said the brothers' elderly mother lived in the house and used a wheelchair but was not usually home in the afternoon.
Walko, 55, said he thought the explosion was a plane crash. It shook his house and knocked pictures and clocks off the walls, he said.
"It was just unbelievable. I never experienced anything like that in my life," Walko said.
Walko said he ran across the street and found one brother under a couple of boards. He removed the lumber and said the man complained of back pain. The other brother was found in the basement.
Firefighters and gas utility workers were investigating. Chris Brown, a spokesman for gas company UGI Utilities Inc., said workers could not find any elevated gas readings after the blast.
Slideshow archive | ABC13 wireless | Help solve crimes