[ExxonMobil fire aftermath: What we know, don’t know about cause, fuel production, more]

A fire erupted inside the massive ExxonMobil refinery in north Baton Rouge before midnight Wednesday, lighting up the sky and casting an orange glow visible from miles away but causing no injuries, according to initial reports from first responders and company representatives.

The fire was completely extinguished by 7 a.m.

Baton Rouge Fire Department spokesman Curt Monte said at a news conference around 1 a.m. that no explosion had occurred and no one was injured.

Denny Butler of Zachary, who was driving home from work on nearby Interstate 110, said "the whole sky lit up, bright enough to be daytime." But he kept driving toward the plant, hoping his friends who work there were alright. He figured that "if Exxon really blows up, we're all gonna be dead anyway."

An ExxonMobil spokeswoman said the fire was isolated to the area where it began.

"ExxonMobil will continue to actively monitor the facility fence line and air quality in the surrounding areas of the North Baton Rouge community," Danny Lee, a public affairs advisor for the company, said in a release Wednesday morning. "All readings are non-detect."

Company representatives at the scene said Exxon will begin investigating the cause of the fire as soon as it is completely extinguished. They said additional information will be released when it becomes available.

Media representatives gathered at the entrance of the plant early Wednesday, in a spot where flames weren't directly visible but flickering orange smoke reflected against overcast skies. The air there bore no particular odor.

Officials declined to speculate about what could have caused the fire.

Monte said there was no impact beyond ExxonMobil's property line. He said the company's volunteer firefighters, who are Exxon employees, are handling the firefighting efforts and hadn't requested assistance putting out the blaze.

However, the Baton Rouge Fire Department's hazardous materials team is monitoring air quality readings in the area and as of early Wednesday reported that all were below detection limits, officials said.

A representative from the state Department of Environmental Quality was also on scene.

ExxonMobil tweeted around 12:25 a.m. Wednesday that fire crews had contained the blaze "to the area where it occurred." 

"We are monitoring air quality at the fence line," the tweet said.

The Exxon refinery, a longtime staple of the Baton Rouge community, was rocked with a series of explosions during a significant cold snap Dec. 31, 1989, that killed two people. Those blasts could be felt miles away.

ExxonMobil has had a significant presence in the city for nearly 111 years. Then known as Standard Oil, the company announced in April 1909 that it would site a refinery in north Baton Rouge, and began operations seven months later. In the years since, it has expanded beyond oil refining and opened chemical, resins finishing, polyolefins and plastic plants, creating a massive and wide-ranging operation that remains a major local employer.

Baton Rouge's ExxonMobil facilities had about 7,000 workers in 2018, including contractors. More than 3,000 worked in the refinery as an employee or contractor, according to the company.

Many residents reported hearing an explosion as the early Wednesday fire erupted, though officials disputed that characterization of the incident. 

Stay with theadvocate.com for more updates. 

Contact Katelyn Umholtz at kumholtz@theadvocate.com.