The mine collapsed in August 2007, killing and entombing six workers and another three rescuers 10 days later.

Also left inside the mine was the underground equipment used to extract coal from the seam approximately 1700 feet underground.

The suit, brought by the insurers for Murray Energy’s partner on the operation Intermountain Power Agency, was filed Thursday in the 3rd District Court of Utah against Murray Energy, its Utah affiliates and a Colorado-based engineer, according to the Associated Press.

The lawsuit does not contain financial information or bring forth any new allegations, but demands that the producer pay for the equipment shuttered underground when recovery efforts were called off.

The insurers said in the claim that IPA was reimbursed for the lost equipment, but that they wanted their money returned. They also blamed Murray Energy for the disaster by repeating findings of federal investigators, the news service said.

Additionally, the plaintiffs said no accounting existed that would provide a total loss amount, but an attorney involved said the machines were worth millions of dollars.

Murray Energy acknowledged the June 24 lawsuit filing to ILN, calling the claims and charges “completely baseless”

“The company will vigorously defend against the lawsuit”, business development and external affairs vice president Rob Murray said.

He also noted that, due to Murray’s policy not to comment on pending litigation, the company would make no further statement on the situation.

Kerry Allred, Manuel Sanchez, Louis Hernandez, Carlos Payan, Don Erickson and Brandon Phillips died in the initial incident at Crandall Canyon. Gary Jensen, Brandon Kimber and Dale Ray Black were killed in the second collapse.

Crandall Canyon's co-owner with IPA is UtahAmerican Energy, a Murray Energy subsidiary.