Balls of fire and walls of propellant-fueled flame virtually destroyed a Tremont concrete plant Thursday as firefighters could do little more than watch.

Two of four metal-frame buildings that comprised the ICCI Illini Concrete, off Illinois Route 9 on the village’s west end, were consumed by the blaze and at least a third was damaged after it erupted shortly after noon.

No one was injured, as the company’s general manager evacuated the buildings of about half of its 20 employees after he discovered the fire already in full force.

“I heard a loud bang” in the main building,” said Jim McCoy as he watched the blaze with owner Jim Welter. “I went back there, and the roof was on fire. We went running through the buildings, getting everybody out.”

“We have no idea” yet what ignited the massive blaze, Welter said.

He estimated it destroyed “a couple million” dollars worth of buildings and equipment — “forklifts, concrete batch plants, rebar benders, air compressors, tools. It’s all gone.”

“This is crazy. I hate to see this happen,” employee Christopher Darnell of South Pekin said as hissing fumes roiled flames into one building’s collapsing roof and ignited barrels of flammable liquids. 

When they exploded, balls of flame rose above the building.

“That was a 55-gallon barrel of hydraulic fuel” near the main building’s front entrance, Darnell said when one explosion, felt 70 yards away from the building, sent flames shooting through the roof.

Above the plant, thick black smoke rose into the day’s southern breeze, marking the fire’s location from miles away across harvested farmfields.

Tremont firefighters, joined by about a half-dozen other area departments, were virtually powerless in controlling the blaze at it spread from the plant’s main building to two others on each side.

A hose extended at least 100 yards from the plant down Route 9 to the closest hydrant, providing a minimal water supply that firefighters augmented with water tankers. Firefighters poured what they could onto the buildings, but were forced to keep a safe distance from the buildings and their volatile contents.

Rain earlier Thursday prompted the plant to cancel work for the day for its workers assigned to pour concrete in facilities behind the buildings, Welter said. 

The firefight continued several hours after the blaze erupted. Official comments from its coordinating chief were not yet available.

Welter and Darnell said the plant, which opened in 2008, was currently making concrete bridge beams for the Illinois Department of Transportation.

“I don’t know” about the future of the business in the fire’s wake, Welter said.

“We still have contracts to fulfill,” he said. “Until we assess what we’ve lost, I don’t know what we’ll do.”

Follow Michael Smothers at Twitter.com/msmotherspekin