SANFORD — A massive, fast-moving fire tore through a long-abandoned mill building on River Street in Sanford on Friday night, destroying the mill and a link to the city’s textile history.

The fire at the building, known locally as the Stenton Trust Mill, was reported about 6:50 p.m. and spread quickly, with flames leaping from the windows and smoke filling downtown.

Assistant Fire Chief Steve Cutter said there were no reports of injuries, and the cause of the fire was under investigation. Investigators from the state Fire Marshal’s Office and the federal Bureau of Alcohol, Tobacco, Firearms and Explosives were on hand.

Video courtesy of Kathleen Boisvert

One of the mill’s walls was bowing, and firefighters were concerned that it might collapse. They planned to be on the scene all night, hosing the mill with water from ladder trucks. They also were concerned the fire might spread to an adjacent mill building, which also was vacant, and planned to use a drone to look for hot spots.

“We’ll be putting water on it all night,” Cutter said. “We won’t be able to get in there until morning.”

More than 100 firefighters from 20 communities helped to battle the blaze, which attracted hundreds of people who recorded the fire on their phones and shared images on social media.

Cutter said it was the largest fire in Sanford that he could remember.

Eyewitness Warren Royea, 28, who lives in an apartment directly across from the mill on Spruce Street, noticed the fire about 6:45 p.m., and notified a police officer who had just made a traffic stop in the neighborhood.

“I heard it before I saw it,” Royea said. “It didn’t take long at all. It spread in minutes.”

The heat was so intense that Royea moved his vehicle from one side of the street to the other.

David Cameron, 27, also lives across the street from the mill. He left his second-floor apartment about 7 p.m. and saw a wall of flames. “It was pretty intense,” he said. “I’ve never seen a fire like this. Everything that could be burned is now gone. It’s just steel.”

The neighborhood was covered in ash, and firefighters doused nearby houses with water to protect them.

Cutter said firefighters fought the blaze from ladders because it was unsafe to enter the building. He called the strategy “an exterior defensive attack” designed to contain the blaze to the mill and prevent it from spreading. The bowing wall and the concern that it might collapse prompted firefighters to move their equipment back from the building.

Cutter said he had no information about the cause of the fire, and declined to speculate. The mill was fully engulfed when firefighters arrived, he said. He suggested that it might have spread so quickly because of “oil-soaked floors” and debris that had been left in the mill.

City Manager Steve Buck wasn’t sure of the mill’s history. He believed it was built in the 1900s, and it has been abandoned for decades.

Sanford thrived in the late 1800s when the Goodall Mills dominated the city’s downtown. The mill complex founded in 1867 by industrialist Thomas Goodall was the first in the country to manufacture fine dyed wool fabrics and, from the 1890s to 1910, was the catalyst that brought a wave of French Canadian immigrants to Sanford.

The mill closed in 1955, costing the city more than 3,500 local jobs, and Sanford has struggled to revive its economy since then.