[SheepWhisperer]

To my knowledge no possible cause has yet been identified.
~~~~~

Videos from security cameras at two different locations show flames/sparks under one of the cars as it rolled by, before the derailment.

[just Grace]

Videos from security cameras at two different locations show flames/sparks under one of the cars as it rolled by, before the derailment.

——
I wonder if it was eco-terrorism?

[robowombat]

That would sound like a hotbox on one of the tank cars. If so there will be a post mortum one was the packing insufficient or was the journal box not inspected correctly or on time. It could take quite a while to fix blame.