Amazing footage of train crash near Rudine in Croatia when the service vehicle arriving to help in train crash that happened few moments earlier also crashed into misfortune train. 6 of about 156 passengers have died.
Passengers were notified that breaks dont work on the downhill just before the crash.

Update: It Becomes more obvious that the main reason for both accidents is a liquid sprinkled on railroad tracks, which is commonly used against the weed so it would not catch fire when braking. Railroad workers claim that it should take 4 hours for liquid to dry but eyewitnesses claim that the railroad was greasy even the day after. The theory is confirmed by the train operator that was sent to pick up passengers after the accident, and it began to slide backwards in the proximity of accident site.
Liquid was most likely sprayed by the same vehicle crashing in this video, as you can see that tank it was carrying was damaged in the crash.
Greasy track: http://img401.imageshack.us/i/railm.jpg/ (less info)