Billowing black smoke seen for miles as massive Walmart distribution center burns in Indiana

Large plumes of thick smoke soared into the air in Plainfield, Indiana, on Wednesday after a 1.2 million-square-foot Walmart distribution center caught fire.

The structure fire began around 1 p.m. Wednesday, according to a Facebook post from the Avon Police Department. The building was fully engulfed in flames by the time fire authorities arrived.

Smoke from the fire could be seen from miles away — and even on satellite imagery — as the fire grew in the town near the Indianapolis International Airport.

One firefighter suffered minor injuries while fighting the fire but was treated and released back to the scene, Plainfield Fire Chief Brent Anderson said.

The Bureau of Alcohol, Tobacco, Firearms and Explosives will be the lead agency in investigating the cause of the fire, which could take weeks, according to the fire chief.

"Right now we have no idea what may have started this (and) no reason to believe it's suspicious or anything," Anderson said.

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Mario Cruz, who has worked in the stocking department for three years at the distribution center, said they stocked everything from clothing to food to electronics at the distribution center and that there is always a lot of cardboard inside.

Deputy Chief Joe Aldridge of the Plainfield Police Department said Walmart believed all 1,000 employees at the distribution center were accounted for and that they got out of the building safely.

“It’s going to be difficult to contain this,” he said. “If you live in neighborhoods north of this facility, I’d say you should stay indoors and keep your windows and doors shut.”

Fire officials warned the distribution center was full of items that could become toxic if burned. The Indiana Department of Environmental Management and the Environmental Protection Agency arrived Wednesday to assist in testing for hazardous materials and air quality issues from the fire, the fire chief said.

"We are going to err on the side of caution right now," Anderson said. "We will treat everything as if it's hazardous."

The fire department said the firefighting operation is expected to last well into Wednesday evening.

Contributing: The Associated Press

This article originally appeared on USA TODAY NETWORK: Indianapolis Walmart fire: black smoke seen from miles away