A fire official says a massive blaze at a plant south of Dallas is nearly contained and about 1,000 residents who had been forced to evacuate are being allowed to return to their homes.
The fire broke out before 11 a.m. Monday at a Magnablend Inc. facility in Waxahachie. No serious injuries were reported.
Waxahachie Fire Department spokeswoman Amy Hollywood said Monday evening the blaze was 95 percent under control in the North Texas city 30 miles (50 kilometers) south of Dallas.
Officials say the fire was sparked as workers mixed chemicals.
Waxahachie Fire Chief David Hudgins said it wasn't immediately clear what chemicals were involved in sparking the fire, but crews expected to quell the flames by late afternoon and allow about 1,000 evacuated residents to return to their homes in the city 30 miles south of Dallas.
"It's the building that's burning, and there's chemicals inside, multiple kinds of chemicals," Waxahachie Fire Department spokeswoman Amy Hollywood. "Saying which kind would be speculative."
Nicolas Brescia of the U.S. Environmental Protection Agency said air quality readings in the city of about 25,000 did not require further action but that officials would continue monitoring to ensure hazardous materials did not spread outside the plant.
Magnablend spokesman Donald Golden told WFAA-TV that the 25 to 30 employees who were inside a warehouse at the plant evacuated safely when the fire broke out before 11 a.m. Golden said the company manufactures about 200 products, including some that are hazardous when ignited, but there was no immediate word on what caused the blaze.
Authorities had ordered residents closest to the plant to evacuate, while others were advised to stay inside with doors and windows shut.
Jessenia Colin, an assistant general manager at a nearby Hampton Inn and Suites, said hotel staff members turned off air vents so smoke and chemicals didn't enter the rooms. As they waited for news and watched the smoke billow, staff covered their mouths to protect against the heavy chemical smell that hung in the air.
"It smells like a whole bunch of chemicals, like wrappers burning," Colin said. "It's making everyone's heads hurt."
Stephanie Otto said she was preparing her new restaurant for a Tuesday opening about a quarter-mile from the plant when she heard sirens and walked outside to see a "huge plume." She said she could hear what sounded like gun shots for about 15 minutes, and there was a strong smell of ammonia.
"It was huge," Otto said. "It looked like an atomic bomb went off."
Ellis County emergency management officials issued a mandatory evacuation order for an apartment complex, an elementary school and a junior college. Sheriff's officials urged residents not to drive toward the area of the fire.
Magnablend, Inc., manufactures, blends and packages chemicals. Much of its business revolves around energy production, including chemicals used to stimulate oil and gas wells and hydraulic fracturing. The company was launched in Waxahachie in 1979 and now employs about 250 people, with operations in Pennsylvania, Wyoming and North Dakota as well as Texas.
Texas Commission on Environmental Quality spokeswoman Lisa Wheeler said Magnablend has been in compliance with its state permits. A search of public documents revealed no significant violations for the company.
Associated Press writers Schuyler Dixon and Danny Robbins in Dallas, Ramit Plushnick-Masti in Houston and Jennifer Garske at the Broadcast News Center in Washington contributed to this report.