WASHINGTON - The National Transportation Safety Board investigators say they expect to publish a preliminary report in two weeks on the Norfolk Southern derailment.

The NTSB announced on Tuesday that they have located the rail car that caused the derailment on February 3.

According to an update from the board, surveillance video from a residence showed what appears to be a wheel bearing in the final stage of overheating moments before the derailment.

The wheelset from the suspected railcar has been collected as evidence for metallurgical examination, according to the NTSB.

The tank cars are currently being decontaminated. Once decontamination is complete, NTSB says investigators will return to Ohio to examine the tank cars.

The vinyl chloride tank car top fittings, including the relief valves were removed. Once the fittings are examined by NTSB investigators, they will be shipped to Texas for testing, which will be conducted under the direction of the NTSB.

NTSB has obtained locomotive recorder data, forward- and inward-facing image recording data and wayside defect detector data. NTSB investigators continue to review documentation, event recorder data and perform interviews.

Thirty-eight rail cars derailed in the crash and a fire broke out which damaged an additional 12 cars.

There was a total of 20 total hazardous material cars in the train, eleven of which derailed.

A list of what the derailed rail cars were carrying may be seen below.