Federal investigators say the fiery collision between a commuter train and an SUV that killed six people in the New York City suburbs cost the railroad about $3.7 million.

The National Transportation Safety Board's preliminary report into the accident was released Monday. It says about 480 feet of third rail was damaged in the crash, as well as the lead railcar.

The Metro-North train crashed into a Mercedes SUV on Feb. 3 at a grade crossing in Valhalla. The impact sparked an explosion and fire that burned out the first car of the train and sent pieces of third rail through the passenger area. The SUV driver and five men on the train died.

Such preliminary reports from the NTSB rarely include major disclosures or conclusions. Those could be several months away.