Today, a German-Dutch* InterCity Express (ICE) train collided sideways with an empty freight train in Eastern Netherlands (see here, or in Dutch with photos here or here) — it is good to know that nobody got hurt but we can still only guess what could have happened.
*ICEs are all Siemens-built German trains, but some trains in cross-border service are registered at partner operators, such as the Danish State Railways (DSB) or, in this case, the Dutch high speed operator NS Hispeed.
If you look at the pictures, you see the ICE headlights and the end of the freight train without an engine, so the two trains were traveling in the opposite direction. You can see that the ICE front remains intact, so it was not a frontal or a head-tail collision, but the train is scratched long on the side, which means that either one of the trains derailed before the collision or — I think more likely — the ICE was diverted by a switch or a track merge to a track already occupied by the freight train.
This latter hypothesis is supported by the location – see on Google Maps and find the switch #5105 (good luck) on this topological map on Sporenplan.nl (on the bottom, right of “Zv”). Here, an empty freight train heading West to the Rotterdam port needs to cross the route in level of a passenger train running to the East. The freight train didn’t completely leave the last shared switch when the ICE was already there.
On the railways, such collisions are hard to generate — in areas of switches, interlocking systems make sure that it is impossible for traffic controllers to set conflicting routes. If the freight train received a route diverting to the freight line, this must mean that the last two signals for the ICE were yellow (“reduce speed to 40 km/h”) and red (“don’t pass”). Furthermore, train protection systems make sure that trains cannot pass red signals — although these systems might have some limitations. In case if this line, as the majority of the Dutch lines, the national ATB system is in use, which makes sure that a train is braked to 40 km/h at a yellow light — but does not prevent it from passing the actual red signal.
Considering again the location and the nature of Dutch signaling, I would guess then that the ICE did slow down to a low speed at a yellow signal, but failed to stop (due to human error or maybe brake problems) early enough for the final red signal and crashed sideways to the diverging freight train. Another, far less likely possibility is that the train sensing equipments (axle counters and similar) mistakenly reported that all freight cars have passed, and then a route was already set (i.e. the signal was green) for the ICE train.
Although this is no positive marketing, remember, rail is a very safe industry and within the Netherlands an even safer country — I am just curious.
(Another spectacular but luckily harmless low-speed accident in Holland involving a high speed train was a Thalys incident at Gouda in 2008, which was — also? — caused by missing a red signal, or Signal Passed At Danger in rail-speak.)
Update: According to the police, some 300 m of copper wires were stolen before the accident, which might be a cause. Railway safety systems, however, have to be fail-safe, i.e. in case of any malfunction they have to fail on the safe side. In particular, if the train detection system is corrupted signals have to turn red, and in case the signal is blank, the train can only advance at low speed with explicit permission of the train traffic control. So for me the question still remains.