Two companies involved in the deadly 2012 explosion of an oil platform in the Gulf of Mexico have been indicted on federal charges of involuntary manslaughter, the U.S. Justice Department said in a statement on Nov. 19.

Black Elk Energy Offshore Operations LLC and Grand Isle Shipyards Inc. were charged on Nov. 19 with three counts of involuntary manslaughter, eight charges involving federal safety laws and one violation of the Clean Water Act.

Three people and a third company, Wood Group PSN Inc., also face criminal charges related to the explosion, the department said. Those charges include felony violations of the Clean Water Act and other federal safety laws.

The 2012 fire off the coast of Louisiana ignited when workers were welding a pipe on the deck of the shallow-water platform operated by Houston-based Black Elk Energy. The explosion led to the three deaths, several injuries and an oil spill.