(CNN) -- An explosion destroyed a home in suburban Pittsburgh on Wednesday, killing an elderly man and severely injuring his grandchild, authorities said.
A house exploded Wednesday, killng one person and injuring a second, in the Pennsylvania borough of Plum.
The explosion was reported about 1:30 p.m. on Mardi Gras Drive in Plum Borough, about 15 miles northeast of Pittsburgh. Several neighboring homes were damaged, fire officials said.
Richard Leith, 64, was babysitting his grandchild in the home, according to John J. Smith, an investigator with the Allegheny County medical examiner's office. Both were transported to local hospitals, though Leith died later in the afternoon.
The condition of the child, who was treated at Children's Hospital, was unknown, Smith said. Leith's autopsy would be conducted on Thursday, he added.
It is unclear what caused the explosion.
Dave Heiser, a neighbor, told CNN that he was home when he heard the explosion. "I thought my house blew up. My windows were blown out. I went outside and debris was falling from the sky," he said. Watch the neighbor describe hearing the blast »
He said he ran three houses down and saw a woman running with a little girl and screaming.
"The little girl was apparently in the house when the explosion happened and was blown outside," Heiser said. "That house was leveled to the ground. There is nothing left."
Several families who were displaced by the explosion were directed to Red Cross officials to make arrangements for shelter Wednesday night, authorities said. E-mail to a friend
CNN's Ninette Sosa contributed to this report.
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