One of the older buildings in Mount Vernon went up in flames today.

Fire officials say a former convent that has been vacant for about 10 years was heavily damaged this morning. They say they got a call from people who saw smoke coming from the building at 67 South 5th Ave. around 8:15 a.m.

When crews arrived, they found the inside of the three-story building engulfed by flames.

The age of the building made it tough to put out the blaze. “These older buildings were built so well, and it’s really labor intensive opening up walls and ceilings to get to the fire. But I’m sure in its day it was a beautiful building,” says Mount Vernon Fire Chief Al Everett.

It is unknown what started the fire in the basement. Investigators are looking into whether squatters were inside the structure before the fire.