FARGO, N.D. (AP) A Pennsylvania steel company named in a lawsuit over a fiery oil tanker train derailment near Casselton said it should not be held liable for the 2013 accident.

Standard Steel and BNSF are named in a complaint filed by Bryan Thompson, the engineer who was at the helm of the train when it derailed. Thompson said Standard Steel produced a defective axle that contributed to the crash, which he said left him with post-traumatic stress disorder.

The steel company said in court documents that the axles were properly designed and manufactured and that the suit should be dismissed.

“Standard Steel admits that it knew its axles would be used on railcars, but denies that any of its axles were improperly designed or manufactured, and further denies that any of its axles created a substantial risk of harm,' said Elizabeth Sorenson Brotten, an attorney of the company.

A National Transportation Safety Board investigation did not pinpoint the broken axle as the cause of the crash, but the NTSB ordered the industry to recall 43 axles made by Standard Steel in the same 2002 batch.

Thompson's suit said the axle was in “an unreasonably and dangerously defective condition' when it was sold and that the company failed to “adequately warn' Thompson or BNSF.

The accident near Casselton on Dec. 30, 2013, happened when a train carrying soybeans derailed in front of Thompson's train, causing the oil tanker train to also derail. The crash spilled about 400,000 gallons of crude oil and set off a fire that could be seen for miles. No injuries were reported.