WASHINGTON — A fire continued to smolder at a plastics warehouse in Parkersburg, West Virginia, on Thursday evening, nearly six days after it erupted. Local officials have yet to pinpoint what types of chemicals and materials went up in the flames.

The 420,000-square-foot facility, formerly the Ames Tool Plant, is owned by Intercontinental Export Import Inc. and was being used to store various plastics and other items, according to state officials. The building caught fire early Saturday morning, and firefighters have been working to put it out ever since.

The state’s Department of Environmental Protection on Thursday ordered the owner of the facility to “immediately” provide a detailed inventory of all materials that had been stored there, as well as at its other facilities.

The 27-page order details numerous violations at the warehouse in recent years. In 2008, two volunteer firefighters warned in a report about the potential for a fire at the facility, saying they had “extreme concerns,” the Charleston Gazette-Mail reported Thursday.

State officials say air samples have detected pollutants “at levels comparable to or lower than what is typically seen in urban areas.”

“We have done multiple, multiple, multiple testings of the air and all. So far, the multiple testings are OK,” Republican Gov. Jim Justice said at a news conference Tuesday.

Local residents, however, are concerned about potential threats to their health.

David Wright told HuffPost that “the smell of burnt plastic comes and goes with the wind.” And like his neighbors, he’s worried about what may have made it into the air.

“Now that it’s died down a little bit,” he said of the blaze, “I wonder who is going to pay for all the firefighting efforts.”

Jessica Scritchfield Wooten, a medical field employee who had a baby in Parkersburg while the warehouse was burning, said the stench was “awful.”

“The air was so bad we had to open our door to ventilate the smell out of our [hospital] room,” she wrote via Facebook.

On Monday, Justice declared a state of emergency in response to the inferno. And at a news conference the following day, he said he was concerned about potential long-term pollution.

“We need all the king’s horses and all the king’s men — the experts from the federal government,” in case they might know something that state officials have missed, he said.

It is unclear what role, if any, the federal Environmental Protection Agency has had in the response. As of Thursday evening, the agency had not put out a public statement on the situation. According to state officials, however, the EPA is involved in ongoing air quality monitoring.

The EPA and Intercontinental Export Import did not respond to HuffPost’s requests for comment Thursday.

Eric Engle, who lives just north of town and is chairman of Mid-Ohio Valley Climate Action, said area schools have been closed all week. State workers have been told to stay home. And residents of Parkersburg and the surrounding counties are anxiously awaiting answers, he said.

“The majority of the people I know have left town,” many to stay with family and friends away from the smoke, he said.

On Thursday, the Mid-Ohio Valley Health Department warned people to “avoid contact with the smoke and remain indoors if possible with windows and doors closed until the smell is no longer detectable.”

Parkersburg, whose population is about 31,000, is no stranger to industrial pollution. The town was the focus of a lengthy 2015 piece in HuffPost Highline.

Paige Lavender contributed to this report.