A train wagon easily weights 20 tonnes and more. If it goes just at 50 kph, it has an impulse of 278.000 kg*m/s. Respectively 278.000 Ns. According to some googling human bones tend to break at around a force of 4.000 N.

Realistically the train is just going to flatten whatever flesh and bones are between the wheel and tracks.

It very well might. But then you have to add the people on the tracks to the death count.