An explosion in a natural gas pipeline southeast of Springfield sent a fireball several hundred feet into the air early Sunday, but caused no injuries, authorities said.

The pipeline break and explosion occurred about 4:40 a.m. in a farm field just north of Pawnee, in eastern Sangamon County, said Assistant Pawnee Fire Chief John Archer.

Archer said the 24-inch pipeline owned by the Panhandle Eastern Pipeline Co. failed at a spot near a creek bed and sent an orange fireball several hundred feet into the air.

Witnesses said they could see the inital fire from several miles away.

Archer said firefighters and hazardous materials workers intially tried to extinguish the fire with foam, but gave up on that effort after Panhandle Eastern workers turned off valves on either side of the break.

"We're just going to let the residual gas burn off before they repair the pipeline," Archer said shortly after 7 a.m.

Archer said one house about 100 yards from the pipeline suffered minor exterior damage from the heat of the fire and several woodlots also caught fire, but were quickly extinguished.

"It's a mostly rural area, so there aren't many people or houses around," Archer said. "We evacuated between 50 and 75 people in the general area, but strictly as a precaution," he said.