The train transported toxic materials from Bulgaria.
Server rferl.org describes that four wagons of a 20-carriage train derailed on December 25 in southeastern Serbia on a section of the railway between Pirot and the village of Stanicenje that is part of the international route from Nis to Dimitrovgrad.
Vladan Vasic, the mayor of Pirot, said that the ammonia leak caused 51 cases with poisoning symptoms: "Seven people were taken to hospital in Nis," he added at a press conference.
Immediately after the derailment, representatives declared a state of emergency. That meant evacuation not only in the city but also on the highway and roads near the place of the accident.
AlJazeera published that the 20-wagon train was carrying ammonia from Bulgaria’s Agropolychim to Serbian fertilizer producer Zorka Eliksir, located in the town of Sabac, 90 kilometers (nearly 56 miles) west of Belgrade.
Ammonia leaked into the air and thick smoke was apparently created. Probably also as a result of this smoke several cars collided on the highway.
The circumstances of the accident are under investigation. The cause has been known yet.
