Human remains are found inside an SUV that officials say caused pipeline fire in suburban Houston

DEER PARK, Texas — Human remains were found inside an SUV that authorities say hit an aboveground valve on a pipeline in suburban Houston, causing a fire that has burned for four days, officials said Thursday.

With the fire substantially smaller since it began on Monday, police were able to access the area around the pipeline in Deer Park. Investigators removed the white SUV and towed it away Thursday morning.

While medical examiners with Harris County were processing the vehicle, they recovered and removed human remains found inside, Deer Park officials said in a statement.

“They will now begin working through their identification process, which will take some time,” officials said.

Officials say the underground pipeline, which runs under high-voltage power lines in a grassy corridor between a Walmart and a residential neighborhood in Deer Park, was damaged when the SUV driver left the store’s parking lot, entered the wide grassy area and went through a fence surrounding the valve equipment.

But authorities have offered few details on what caused the vehicle to crash through the fence and hit the pipeline valve.

Energy Transfer, the Dallas-based company that owns the pipeline, on Wednesday called it an accident. Deer Park officials said preliminary investigations by police and FBI agents found no evidence of a terrorist attack.

The pipeline is a 20-inch-wide (50-centimeter-wide) conduit that runs for miles through the Houston area. It carries natural gas liquids through Deer Park and La Porte, both of which are southeast of Houston.

The valve equipment appears to have been protected by a chain-link fence topped with barbed wire. Energy Transfer has not responded to questions about any other safety protections that were in place.

Officials say they expect the fire to be extinguished sometime Thursday evening.

Authorities evacuated nearly 1,000 homes at one point and ordered people in nearby schools to shelter in place. Officials began letting residents return to their homes on Wednesday evening. Residents could be seen at their homes Thursday morning, assessing damage.

A portion of a highway near the pipeline would remain closed, officials said.

Energy Transfer and Harris County officials have said that air quality monitoring shows no immediate risk to individuals, despite the huge tower of billowing flame that shot hundreds of feet into the air when the fire first began, creating thick black smoke that hovered over the area.