FALL RIVER, Mass. (WPRI) — An investigation is underway after a fire tore through a long-vacant Fall River building Tuesday evening.

Fall River District Fire Chief Scott Flannery tells 12 News firefighters spent nearly three hours knocking down the flames.

Though the Brightman Street commercial building has been boarded up for years, it most recently housed a casket manufacturer. Prior to that, it was home to the historic Royal Theatre.

Flannery said the department has been preparing to respond to this building for quite some time.

“We’ve pre-planned this fire a couple of times,” Flannery explained. “We had a good feeling it would eventually catch fire and it did.”

The flames were so intense that firefighters weren’t allowed inside the building to see if anyone was inside.

“We never got inside, it was just going too good and it was too dangerous to get guys in there and look for anybody,” he said. “There are some vagrants who have been known to live in there and have fires … We hope no one was in there, but it was just too dangerous.”

Flannery said the building, which dates back to the 1800s, has been deemed a total loss and will eventually be demolished.

“They’re definitely going to tear it down, which will be great,” Flannery said. “It’s been a hazard for a long time.”

It’s unclear at this time what caused the fire.