The head of the Shanghai Railway Bureau, during a meeting with the investigation team set up by the State Council to investigate the causes of last Saturday's train crash, said that initial investigations show that a signal light at Wenzhou South Railway Station was not working properly. The signal light was red when it should have been green. Moreover, it did not give the signal it should have given to the coming train. Railway employees did not give any warning either. All these factors led to the train crash.
 
Source
CCTV

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