A man and woman were blown out of their Montgomery County house early Wednesday morning when the home exploded, according to neighbors.

Investigators said the explosion in the 11000 block of Ashley Drive in Rockville, Md., was accidental and caused by renters of the home, who were converting a clothes dryer from gas to electric, which caused a gas leak. The gas leaked for at least a few hours before something ignited it, causing the explosion.

The man and woman who were inside the home were severely injured and burned, according to neighbors. The woman was thrown into the back yard, John Schriffen reported. Officials said the victims should survive their injuries but are listed in critical condition.

Debris flew at least 50 yards in each direction in the explosion, but no one else was injured.

Large portions of roof were hanging from treetops and boards with nails and pieces of broken glass filled the streets.

"I just looked out the front window and I couldn't believe it. The house was gone," neighbor Tom Harding said. "Everything was in flames. I'm still in shock about this."

All utilities companies were at the scene and the power and gas was shut off throughout the neighborhood until investigators could pinpoint what caused the explosion.

Neighbors said the couple moved into the house just a few days ago.

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