Robbins Lumber in Maine had experienced multiple fires and a recent workplace safety citation before a fatal explosion Friday.The Maine State Fire Marshal's Office said the explosion at the mill in Searsmont, Maine, killed a firefighter and left several people in serious and critical condition.Searsmont, a town of about 1,500 people, is about 95 miles from Portland, Maine.Sister station WMTW's 8 Investigates found at least three fires connected to Robbins Lumber in recent years.In 2019, multiple fire departments responded to a fire inside the mill’s ash building. At the time, the Lincolnville Fire Department posted on Facebook that it involved "hot ash, nothing too serious."Video below: Maine lumber mill explosion kills firefighter, leaves several in critical conditionAccording to reporting by the Penobscot Bay Pilot at the time, the fire started after hot ash from a biomass plant was piled too high in a storage area.The mill also experienced two fires in 2024, including one in March, according to a Facebook post from the Morrill Volunteer Fire Department, and another in November.The Penobscot Bay Pilot reported the November fire broke out in a control room that managed airflow and heat for one of the mill’s two kilns. The room contained boiler pipes and computer equipment.Even more recently, the Occupational Safety and Health Administration cited Robbins Lumber in 2025 for failing to follow preventative safety procedures related to the control of hazardous energy.Video below: Drone video shows incredible fire at Robbins Lumber mill in Searsmont, MaineAccording to an OSHA violation filed last June, the mill failed to conduct an annual inspection of its energy-control procedures. The citation also said the company’s procedures did not clearly explain how to shut down, disconnect and isolate machinery capable of releasing hazardous energy.The OSHA website shows that Robbins Lumber later reached an informal settlement agreement, which came with a $5,426.50 fine. WMTW's 8 Investigates spoke to a member of the Northeast Lumber Manufacturers Association who said this was a small mark on a long history of stellar safety inspections. Maine has seen several major industrial emergencies in recent years.In 2020, a massive explosion shut down the paper mill in Jay. Federal investigators later determined the blast was caused by corrosion and cracking on a pulp digester. Investigators also blamed ineffective inspection and repair practices for the catastrophic failure.In 2022, a massive fire destroyed much of the Penobscot McCrum potato processing plant in Belfast. The Maine State Fire Marshal’s Office ruled the fire accidental, but investigators said the damage was so extensive that they could not determine an exact ignition source.It will likely be some time before officials determine a possible cause behind the Robbins Lumber explosion. Video below: Owner of Searsmont, Maine, mill gives statement following devastating fire