Pine Ridge, SD – PINE RIDGE, S.D. – Four people are confirmed dead and with even more injured after a propane explosion on the Pine Ridge Reservation. Among the dead are an elderly man and woman and two younger women.

Oglala Sioux Tribe spokesperson Kevin Yellow Bird Steele said an East Ridge duplex exploded Thursday afternoon, caused by a leak under the home. Yellow Bird Steele said three or four other people were transported by helicopter to area hospitals. The search continues for a number of people who are still missing.

Witnesses said the explosion shook the ground and completely destroyed both units of the house. Authorities tell NewsCenter1 that the explosion occurred when a Housing Authority employee attempted to light a propane furnace. Further reports indicate that the heating units were on inside the house when the main valve of the propane tank was opened, filling one or both units with propane gas prior to the explosion.