A train controlling rail tracks loose contact with rail. This is a train does regular checks on track and tunnel used for YHT (Yüksek Hızlı Tiren - high speed train).

Authorities say it left track just entering tunnel hits the wall in entry and drag in tunnel for 200 meters.

Authorities investigate reason.

https://www.youtube.com/watch?v=gEjBGe9aFgw

https://www.dunya.com/gundem/bilecikte-kilavuz-tren-tunelde-raydan-cikti-2-olu-haberi-453728