Nobody was injured during a 3-alarm blaze last night at 19 Everett St. and officials are invesitgating how it stared, according to the Waltham Fire Department.

Nobody was home at the time of blaze, according to Waltham Fire Department Lt. Michael Murphy. Only the upstairs unit of the two-story home was occupied. Area neighbors told Waltham Patch that Roni-Beth Shapiro lives in the upstairs floor, but was in Florida when flames struck. Shapiro owns the home, according to city records.

The state Fire Marshal is helping firefighters investigate the cause of the fire, Murphy said.

The home sustained heavy smoke and water damage, Murphy said. Firefighters had to cut into the roof, left side of the house and break many of its windows. The home was boarded up sometime after the fire and piles of home items laid on the ground next and in front of the home this morning. Murphy said firefighters encountered a lot of home contents burning when they entered the house.

The fire was reported at 7:17 p.m. and when firefighters arrived four minutes later, they saw smoke and flames shooting from the basement and up the left side of the home, according to Murphy. By 8:22 p.m. the blaze was declared three alarms with additional Waltham firefighters being called in with each new alarm. Firefighters knocked the majority of the fire down by 10:04 p.m., Murphy said. Crews cleared the scene by 3 a.m.

Crews from Watertown, Lincoln, Belmont, Newton, Lexington, Weston, Cambridge, Arlington and Wellesley assisted by either responding to the scene or providing coverage for the remainder of Waltham, according to Murphy.