20 City firefighters battled a blaze on Victoria Street in the North End today.
The call came in just past 3:30 as an outside fire but, was upgraded to a structure fire once crews arrived to investigate.
The fire was at the back of the building and in the attic.
12 to 14 people who live will be displaced tonight at least and the Red Cross is assisting them.
No one was hurt but, a dog was rescued from the building.
The cause of the blaze is under investigation.