A pipeline explosion sends a towering pillar of flame over Houston's suburbs

Local authorities would not speculate at an afternoon news conference about what caused the fire and what role a burned car near the source of the flame may have had. Energy Transfer said in its statement that it was "aware of early reports" that a car had struck some valve equipment but did not offer more details, including the origin of those reports.

Firefighters were dispatched at 9:55 a.m. after an explosion that rattled adjacent homes and businesses in Deer Park and La Porte, about 25 miles (40 kilometers) southeast of downtown Houston, long the energy capital of the U.S. The plume of smoke could be seen from at least 10 miles away.

The only injury reported so far was to a firefighter who sustained a minor injury, officials said.

Geselle Melina Guerra said she and her boyfriend heard an explosion at around 9:30 a.m. as they were having breakfast in their mobile home. "All of a sudden we hear this loud bang and then I see something bright, like orange, coming from our back door that's outside," said Guerra, 25, who lives within the evacuation area.

Her boyfriend woke up his brother and they ran to their car.

"I was just freaking out, pacing around the living room, not really knowing what to do or what was happening," Guerra said. "I thought maybe it was an airplane that had crashed down by our house."

La Porte city spokesperson Lee Woodward told KTRK-TV that people in nearby schools were told to shelter in place as law enforcement blocked off a wide area.

Energy Transfer said in a statement that air monitoring equipment was being set up in the area.

At nearby San Jacinto College, which closed its campus after the explosion, people who gathered included Evan Wyman, who had gotten word after calling police that her dog, Baxter, and had been rescued from her home, which is in the evacuated neighborhood.

"I just know that my dog is rescued," Wyman said.

Houston is the nation's petrochemical heartland and is home to a cluster of refineries, plants and thousands of miles of pipelines. Explosions and fires are a familiar sight to residents in Texas' largest city, including some that have been deadly. The blasts have raised recurring questions about the adequacy of the industry's plans to protect the public and the impacts of environmental damage.

Video images from KTRK showed a park near the fire had been damaged and firefighters pouring water on adjacent homes. By noon, at least a couple of homes appeared to have caught fire, with smoke pouring from their roofs. There are also several businesses nearby, including a Walmart.

Sanchez said they're used to evacuations because they live close to other plants near the highway, but he hadn't seen an explosion before in his 10 years living there.

"We just drove as far as we could because we didn't know what was happening," Sanchez said from a parked car at a gas station near his college.

Officials have ordered residents in the Brookglen neighborhood area near the fire to evacuate, Woodward said in an email.

"Please avoid the area and follow law enforcement direction. Further details will be released as available," Woodward said.

The fire burned through high voltage power lines, and the website PowerOutage.us said several thousand customers were without power in Harris County.