St. Joseph, Mo. ? Eleven of the 14 construction workers injured in an explosion at a new pork processing plant in St. Joseph have filed a lawsuit seeking unspecified damages from six defendants.

The Oct. 12 explosion at the nearly completed $130 million Triumph Foods plant killed one worker. The state fire marshal found that gas leaking from an open valve fueled the blast. The fire marshal’s report listed halogen lighting, fans in the ductwork of the heating system and a striker and torch found in the hallway of the kitchen as possible ignition sources.

The lawsuit, filed Thursday in Buchanan County Circuit Court, lists 66 counts of negligence. In addition to Triumph Foods, defendants are Missouri Gas Energy, of Kansas City; A. Epstein and Sons International, of Chicago; IHP Industrial, of St. Joseph; Superior Air Handling, of Clearfield, Utah; and Dragoo Metal Works, of St. Joseph.

Triumph Foods and IHP Industries had no comment Friday, and Superior Air Handling said executives were in a daylong meeting and nobody was available to comment. Calls to a spokeswoman for Missouri Gas Energy and Dragoo were not returned Friday. David Kornelis, an attorney for Epstein and Sons at the Armstrong Teasdale law firm in Kansas City, said he could not comment on the lawsuit.

The suit alleges the defendants didn’t conduct repairs, service work, testing, inspections, gas pipeline installation, equipment hookup or plant operation in a proper manner.