FALL RIVER, Mass. (WPRI) — An investigation is underway into the cause of a massive fire that destroyed a Fall River power tool shop Monday night.

Every firefighter available in the city rushed to Mariano Bishop Boulevard just before 9 p.m. to find heavy flames and smoke billowing from the roof of Burns Power Tools.

The power tool shop, which has been in business since the 1930s, sustained significant damage and has been deemed a total loss, according to Fall River Fire Chief Roger St. Martin.

There were “a couple hundred” magnesium batteries inside the power tool shop when the fire broke out, according to St. Martin, as well as other potentially explosive materials, which made fighting the fire difficult.

(Story continues below video.)

“There were a lot of small explosions throughout the whole night,” St. Martin said.

St. Martin said firefighters primarily attacked the flames from above, especially after the roof caved in.

Firefighters were seen dumping water onto the burning building from two ladder trucks, which were parked on opposite sides of the business.

St. Martin said while the Subway right next door was also damaged, firefighters were able to stop the flames from spreading to the medical building adjacent to the power tool shop.

That medical building houses an urgent care clinic and an optometry practice.

Dr. Christina Herald, owner of Fall River Vision, tells 12 News she’s grateful her business was left unscathed.

“It’s a miracle,” Herald said. “I was watching them pour water all over it last night … and all of our expensive equipment and medical records are all right here.”

“There are no words,” she continued. “My whole life and dreams are in there … I feel really bad for Burns and everyone who was affected by it, but thank God we were spared.”

(Story continues below gallery.)

The owners of Burns Power Tools, Jeff and Zach Burns, rushed to check on their business Tuesday morning.

The father and son tell 12 News they’re 3rd and 4th generation owners of the power tool shop and are devastated.

Fall River Mayor Paul Coogan told 12 News Burns Power Tools is an institution in the city and they will do what they can to help the business rebuild.

“Burns has been here forever,” he said. “We’ll hopefully get them back on their feet as fast as we can.”

No injuries were reported and the power tool shop has since been boarded up.