A mother and six children, ranging in age from 3 to 11, were killed in an explosion and fire at a central Pennsylvania home, authorities said.Firefighters responded to a report of an explosion and fire at a home in Lamar Township in Clinton County near Mill Hall on Sunday morning.Seven people were trapped, but firefighters could not search the building because it was engulfed in flames, Pennsylvania State Police said in a statement. All seven people died. Police identified them as 34-year-old mother Sarah Stolzfus, four sons, ages 11, 10, 5 and 3, and two daughters, ages 8 and 6.Video below: Neighbor describes hearing a 'boom' in Pennsylvania house explosionThe cause is under investigation. A propane leak inside the home may have caused the explosion and fire, police said, noting that exterior propane tanks did not explode and were not contributing factors to the explosion and fire.The Associated Press contributed to this report.