EAST PALESTINE, Ohio (WKBN) – The National Transportation Safety Board is focused on an overheated wheel bearing in its investigation into the Feb. 3 train derailment in East Palestine.

The rail car that started the derailment has been identified and the bearing that overheated on that rail car is being examined by engineers from the NTSB Materials Laboratory in Washington, D.C., according to an update Tuesday from the agency.

NTSB said it is investigating the wreck itself and not any of the environmental issues. Those are being handled by the Environmental Protection Agency. NTSB will issue safety recommendations if it finds that new protocols should be in place.

Surveillance video from a residence showed what appears to be a wheel bearing in the final stage of overheat failure moments before the derailment.

Tank cars are currently being decontaminated by NTSB investigators. Once the process is complete, investigators will return to Ohio to complete a thorough examination of the tank cars.

Materials including vinyl chloride tank car top fittings, including the relief valves, were removed and secured in a locked intermodal container pending an NTSB examination. Once the fittings are examined by NTSB investigators, they will be shipped to Texas for testing by the NTSB.

As a part of the investigation, NTSB has obtained locomotive event 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.

NTSB said a preliminary report is expected to be published in two weeks.