The United Mine Workers has a new theory on what caused the explosion that killed 12 men at Upshur County's Sago Mine last year.
The union says it wasn't lighting.
The union believes friction between rocks and the metal roof-support system in the mine could have caused a spark that ignited methane gas.
The union presented its report today in Washington, DC, offering an alternative theory to the conclusion of state investigators and the mine's owner, Scott-Depot-based International Coal Group.
The report also lashes out at the federal Mine Safety and Health Administration for what it calls a series of misguided decisions in the months and years before the blast.
It says the agency puts concern about coal company profits ahead of miner safety, and it demands that MSHA re-establish itself as the government's advocate for miners.
The U.M.W. says unlike other coal mine blasts linked to lightning, there was no metal conduit at Sago that could have carried an electrical charge two miles into the mine.
The union says it's more likely that rocks striking metal -- or metal rubbing on metal -- created the deadly spark.
Neither ICG nor MSHA has yet weighed in on the report.