Arson investigators are looking to speak with a witness to Monday's fire in Williamsburg, Brooklyn that killed one person and injured five other residents.

The witness, seen right in a still from surveillance video, was last seen wearing a dark-hooded sweatshirt, dark pants and dark boots or sneakers.

The fire broke out around 4:30 a.m. yesterday at 55 Harrison Place, a three-story apartment building.

Police say a can of gasoline was found outside the building, and surveillance video shows two people entering and leaving the building shortly before it burst into flames.

Sofia Olivo, 17, was trapped by flames on the second floor and died and five other residents received non-threatening injuries.

Witnesses say several people were forced to jump out of windows to escape.