State and federal investigators have wrapped up an initial probe into the fatal explosion and fire at Robbins Lumber in Searsmont earlier this month.
A Maine Department of Public Safety spokesperson said in a written statement Tuesday that investigators believe the fire started at the base of a silo, and is considered "accidental."
Before the fire was contained, a "rapid ignition of suspended particulate material" caused an explosion so powerful it lifted the silo off its concrete base.
Investigators said the silo then toppled over, engulfing the surrounding area in flames and spreading the fire to nearby buildings.
Morrill firefighter Andrew Cross was killed and at least ten other people were injured.
Investigators are expected to continue gathering information in the coming months, as they seek to pinpoint the precise cause of the fire.
