A two-alarm fire at 34 Bellevue St. Friday night also caused extensive exterior damage to the neighboring three decker, the Boston Fire Department reports.

The department says the fire, reported shortly before 8 p.m., was caused by "a spark from frayed wiring on a 2nd floor Christmas tree."

The fire engulfted the tree, burst out a window and climbed up the siding to the third floor, the department says.

No residents were injured.