tunnel, 隧道

Bram Janssen/AP
Islamic State tunnels uncovered
A peshmerga fighter looks out of the entrance of an underground tunnel built by Islamic State fighters. The Kurdish forces found the tunnel in the town of Badana in Iraq which was liberated from the Islamic State group on Monday. The fighters built tunnels under residential areas so they could move without being seen from above to avoid airstrikes. Photo Bram Janssen/AP.
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A peshmerga fighter walks through a tunnel made by Islamic State fighters, Tuesday, Oct. 18, 2016. (AP Photo/Bram Janssen)
Offensive to retake Mosul from Islamic State militants
https://www.yahoo.com/news/offensive-retake-mosul-islamic-state-173010811/photo-p-kurdish-peshmerga-soldiers-walk-photo-143010533.html