HOUSTON -- A pipeline explosion sent flames shooting into the air in northwest Harris County Saturday evening, KPRC Local 2 reported.

Shortly after 2 p.m., a worker driving a bulldozer hit a 31-inch gas line belonging to El Paso Energy’s subsidiary, Tennessee Gas, in a field near Fry Road and FM 529.

Investigators said the driver kept the engine running when he fled after discovering he hit the line.

At about 6:30 p.m., the gas ignited, causing an explosion, El Paso Energy said. A shelter-in-place was issued for a short time.

Witnesses reported seeing the flames all across the Houston area.

Officials said by 9 p.m., the threat was gone.

"There was a ruptured pipeline. It did catch fire, so there was a lot of fire up in the sky. But when the pipeline was blocked in successfully, the line was purged with nitrogen, that fire is out," said Mike Montgomery with the Harris County Fire Marshal’s Office.

The explosion ignited several grass fires near neighborhoods in the area, which were put out around 10 p.m., El Paso Energy said.

No one was injured and there was no structural damage, according to authorities.

An investigation is under way.

The explosion will have no affect on production of natural gas or getting it to its proper places, said EPE. The company also said it shouldn't have any affect on well water in the area.

Authorities said this explosion could have been a lot worse if a full load of gas was going through the line.