Kolkata Metro: The only Metro of IR. কলকাতা মেট্রো : তিলোত্তমার জীবন রেখা ।। - PPG

So the main reason of 12225 derailment looks like illegal way of crossing. In pic we can see mud filling to make temporary way/sort cut for dfc work. Truck just see both side and cross the track, it might had happened that it got chocked or trapped when train comes. This is hieght of ignorance of workers and it happens next to 3kms of a station.
Compeltely fault of negligence of DFC working contractors.
pc;: Twitter

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