The owners of a cargo ship that struck part of a western Kentucky bridge causing it to collapse say they were not responsible for the nighttime crash that took out a chunk of the span because some of the bridge’s lights were not working.

Foss Maritime, which owns the Delta Mariner, made the claim in a federal lawsuit seeking to exonerate itself from any liability from the Jan. 26 wreck on the Tennessee River. The company said the Eggner’s Ferry Bridge lacked lighting for northbound commercial traffic on the river and that only one part was marked with navigational lights.

“The remainder of the bridge was dark,” attorney Bobby Miller of Paducah, Ky., wrote in the lawsuit.

Miller wrote that the ship headed toward the span that had visible navigation lights. The five-story tall vessel struck the bridge just before 8 p.m., tearing away a 332-foot-long chunk and halting traffic.

Seattle-based Foss Maritime put the value of the boat at $13 million, but was unsure how the amount was affected by the wreck.

U.S. Coast Guard in Paducah spokesman Lt. Jennifer Jessee said the cause of the wreck hasn’t been determined yet.

Kentucky Transportation Cabinet spokesman Chuck Wolfe confirmed that that some of the bridge lights had not been operating properly and had been scheduled to be worked on around the time of the wreck. But, Wolfe said, the cabinet is withholding further comment about the lighting until the Coast Guard’s investigation is complete.

Suzanne Lagoni, a spokeswoman for Foss Maritime, described the company’s lawsuit as routine and a “customary practice” after a maritime accident.

Under maritime law, Foss Maritime doesn’t have to sue another party. Instead, it asks a judge to rule on the extent of liability and to halt all other lawsuits and legal proceedings while that determination is made.

The Delta Mariner was carrying an Atlas rocket booster and other components for the U.S. Air Force’s AEHF-2 mission from Decatur, Ala., to Cape Canaveral Air Force Station in Florida, a trip that normally takes about 10 days. The company said the rocket parts were not damaged and there was no change in the scheduled launch date in April.