An explosion early Wednesday at the TPC Group plant near Beaumont, Texas, prompted evacuations and an order that all 16,000 people in one town stay indoors.
Three injuries have been reported, all of them staff at the Port Neches refinery site in East Texas, company officials said.
The Nederland Volunteer Fire Department called for "a mandatory evacuation for everyone within a half mile of the TPC plant" about an hour after the explosion, which happened about 1 a.m. CST.
"This could change and expand to a greater area," the department posted.
In Groves, south of the plant, the Fire Department warned the entire town to "shelter in place." The order was lifted about 6:30 a.m.
While the smoke plume _ which was "coming from unprocessed crude oil" _ was initially directed toward Groves, officials say it has since shifted away thanks to wind directions.
People in Port Arthur north of Highway 73 have been warned to shelter in place, the city said in a Facebook post. Magnolia Avenue, or Highway 366, between Nall Avenue and Spur 136 has been shut down.
"The event is on going, but will be brought under control as quickly and safely as possible," TPC officials said in a statement early Wednesday.
Teams have been sent to the facility's fence line and surrounding neighborhoods to test air quality, officials said.
"Right now our focus is on protecting the safety of responders and the public, and minimizing any impact to the environment."
The plant has been evacuated and all staff members have been accounted for, officials said.
Alica Wolfford Almaraz, who says she lives in Groves, posted photos on Facebook of the fire and reported "select neighborhoods" were being evacuated.
"There was a LOUD boom and huge fire," she wrote. "Lots of reports of blown out windows and house damages. ... lots of freaked out people. Please keep all emergency workers and plant workers in your prayers as they deal with the aftermath."
Tyler Shawn Dunlap says he was asleep when the explosion rattled his home.
"I heard and felt my house shake," he told WTKR-TV. "I first thought people were coming to break in (because) of our intense security so I was scared calling 911."
Others characterized the blast as sounding "like a nuke," according to the news outlet.
The plant is 300 miles southeast of Fort Worth, near the Louisiana border.
