According to Hurriyet article, the tunnel is located in Yusufeli district of Erzurum.

The failure is connected to the Yusufeli dam located in close proximity with the construction site. 

The site was evacuated on Tuesday (29th November) and the collapse occured at 9:00am on Wednesday. 

No fatalities were encountered due to the immediate actions of both the Designer and Contractor's safety engineers.

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