In this day and age this has to be one of the FIRST things to suspect.
As it should, considering recent, Nov 29, 2017, threats by anti-fa in the NW.
Antifa-Anarchists Sabotage Traib Olympia
"Police have raided an Antifa encampment in Olympia, Washington, following a train being sabotaged by anti-fracking activists — but the anarchists claiming credit for the act have vowed to continue until “every officer is down.”