An hour into the movie Lennart and his fellow terrorists realize that the train has been redirected by the police. However, at the end when Lennart releases the poison, he accuses the police to allow a contaminated train to reach the originally planned station.
In the closing sequences of the movie, when Lasko is uncoupling the carriages, there is no sign of any cables, hoses, or other means of conveying the air-conditioning or alarm system between carriages. Since the plot depends heavily on those items, this is important.