Fall River, Ma. On Monday March 30th. Firefighters responded to 288 Plymouth Ave on a box alarm at Cube Smart Self Storage located in a four story granite mill. During a search of the building the crew of Ladder 2 reported heavy smoke on the fourth floor with sprinkler system activation. The sprinkler system was able to contain the fire to one storage unit, while the crews completed extinguishment and overhauled the unit, Command called for the Fire Investigation Unit to respond. Engine 2 tied into the sprinkler system while Engine 4 fed by Engine 9 ran an attack line up to the fourth floor.