COCOA, Fla. -- Firefighters on Thursday brought a fast-spreading tire fire under control at a tire recycling plant in Cocoa.

The blaze sent flames 100 feet high and produced a thick column of smoke that drifted northward from the RMD Americas site off U.S. Highway 1 in north Cocoa near the Beachline Expressway. Officials alerted nearby schools and residents of the potential hazard, Local 6 News partner Florida Today.

The fire on the 20-foot-high pile about half the size of a football field was about halfway out at 1:30 p.m. but no longer poses a threat to surrounding areas, Acting Cocoa Fire Chief Michael Corby said.

It's the fourth fire at the recycling plant since the RMD Americas plant was annexed into the city five years ago, Corby said.

The state fire marshal will investigate the cause of the blaze, which is unknown.

Corby said the fire should be completely out by Thursday night.

The fire was called in at about 10:10 a.m. By the time fire crews arrived, it had spread quickly. Officials at surrounding schools were advised to shut their windows, turn off their air conditioners and keep students inside.

Motorists on U.S. 1 were advised to use caution. Police were prepared to shut down the roadway if the wind shifted that way.

Cocoa, Cocoa Beach, Rockledge and Brevard County firefighters worked to knock the fire back before it spread to surrounding brush and woods. Aerial trucks and tankers were used to suppress the fire with foam.

Patrick Air Force Base firefighters also assisted.

"It's the biggest fire I ever saw," said Larry Childs, a worker at the Goodson Paving plant next to the tire plant.

A precautionary respiratory alert has been issued for residents living north to northwest of the tire plant along Railroad Avenue to Camp and Frontenac Roads.

Corby said the smoke is not hazardous but may be irritating to people who already have respiratory problems.

RMD Americas recycles old tires into rubber mulch.

The state Department of Environmental Protection fined the company $12,500 in February 2006 for violations that included accepting too many waste tires and failing to maintain 50-foot fire lanes around the piles.

Those issues were resolved, said Jeff Prather, spokesman with the DEP in Orlando.

"Their violations were corrected," Prather said.

The company also had no violations when DEP staff inspected the business on Dec. 28 and Jan. 10.

"They were in compliance at that time," Prather said.

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