Mother and six children killed in explosion in Clinton Township, Pennsylvania

Firefighters arrived at an address in Clinton Township, near Mill Hall in the eastern United States, where the home was already engulfed in flames. But the fire was so extensive that rescue efforts could not be launched.

All died in the fire in the Lamar neighborhood, state police said.

The children were between the ages of 3 and 11.

The cause of the fire is under investigation, and authorities suspect leaking propane gas.