Westerly — Firefighters continued to battle a blaze in a retail and residential building on Commerce Street late Friday, three hours after the fire was first reported.

The roof at 3 and 7 Commerce St., off Main Street, collapsed shortly after 9 p.m. The building on the Pawcatuck River is home the restaurant Ten Sandwiches, Mary D's Antiques & Collectibles and several apartments.

All occupants appeared to have made it out safely, though the building's owners were told that two cats had perished in the fire.

Westerly, Pawcatuck and Old Mystic firefighters were ordered to evacuate the two-story wooden structure around 8:45 p.m. The fire was reported around 7:40 p.m.

Pockets of fire continued to flair up throughout the evening.

The building is about 100 years old, according to owners Dominic and Donna DiAngi, who were at the scene. The siblings inherited the building from their grandfather, who built it.

"It's just a shame," said Westerly Town Manager Steve Hartford, who also was at the scene. "I think it's going to be a total loss. They're going to have to take the building down."

No other buildings downtown were in danger of catching fire, Hartford said. The burning building is located right on the river and is surrounded on two sides by parking lots. Part of the building overhangs the water.

Hartford said he had never seen a stubborn fire like Friday's, where firefighters continually poured water onto the flames, only to have it flare back up.

A friend of the owners who did not wish to be identified said that the building recently had undergone a fire inspection and that the owners had added a new fire alarm system.

Patrick Keena of Pawcatuck said he was visiting a friend who lives in the building when the fire broke out.

"We were inside playing video games and the fire alarm went off," Keena said. "We came out, and it was smoking."

Emergency personnel closed West Broad Street in Pawcatuck and Main Street in Westerly, and Stonington police helped divert traffic.

k.florin@theday.com