I’ve since seen video of the explosion. Clearly there was one explosion on or under the roadbed. Whether a truck bomb or a drone I can’t say.
Truck bomb is simplest.
As for the train - if it’s just tankers catching fire, that the engineers could bring it to a clean stop isn’t a surprise.
But that an explosion on the road would ignite a tanker car on the train seems like a lucky accident.
Again there is no surface damage to the roadway. Stop frame at the 2 second mark to see boat bow. When viewing filmed explosions, stop frame is your friend.
A truck bomb could not do the damage we see, without major damage to surface of roadway, and likely could not do any of the damage visible.