Ben Mutzabaugh

USA TODAY

Updated at 12:15 p.m. ET on Monday, July 7.

Montana rail officials say it could take until Tuesday to recover three Boeing 737 fuselages that tumbled down a steep embankment and into a Montana river following a train derailment.

Montana Rail Link spokeswoman Lynda Frost told The Associated Press on Sunday that a crew of 50 workers were using eight heavy equipment machines to recover the fuselages from a steep embankment along the Clark Fork River in western Montana.

Boeing says it and Spirit Aerosystems-- which manufactured the fuselages -- has sent a team of experts to assess the damage from the accident.

"Once we have completed our assessment of damages and determined our next course of action, we will decide what to do with the fuselages," Boeing says in a statement to Today in the Sky.

No injuries resulted from the derailment, which occurred Thursday afternoon. The incident spilled six fuselages that were being carried on rail cars. Three of those slid down a steep bank and into the Clark Fork River. The condition of the other three fuselages was not immediately clear, though pictures from the scene appeared to show damage.

The fuselages were headed to Boeing's 737 assembly line in Renton, Wash.

The Wall Street Journal says the derailment "threatened to throw a wrench in the tightly choreographed and far-flung aerospace supply chain, which depends on just-in-time deliveries of giant parts by train, plane and boat to meet the record demand for jetliners."

Boeing declined comment on how production might be affected by the derailment.

Beyond the fuselages, the Journal adds the train "was carrying components including complete fuselages of six single-aisle 737s, fuselage panels for a long-range 777, and wing parts for a jumbo 747."

"Cars involved in the derailment carrying assemblies for the 777 and 747 have been inspected and their content appears undamaged. They will be shipped to the Boeing final assembly plant in Everett, arriving over the next several days," Boeing adds in its statement to Today in the Sky.

The cause of the derailment is still under investigation.