PENN HILLS — Chief Bill Jeffcoats of the Penn Hills fire department said it took Peoples Natural Gas about five hours to shut off gas service after the blaze at Churchill Center was reported at about 7:30 p.m. Sunday.

Two of the three lines were shut down shortly after utility workers arrived, Peoples Natural Gas community affairs director Barry Kukovich said in a statement Monday. The third shut-off was difficult to locate and complicated to shut off.

Fire Marshal Chuck Miller said four firefighters were hurt when an explosion occurred, and a fifth was taken to a hospital for severe heat exhaustion. A dozen other firefighters were treated at the scene.

Penn Hills Manager Scott Andrejchak blamed the utility’s response for the extent of the damage, estimated by the fire marshal at $1.2 million to $1.5 million.