The long-anticipated campaign to reclaim Mosul from the Islamic State began Monday. It is the largest military operation in Iraq since U.S. forces left five years ago.
The Battle for Mosul
![Peshmerga forces advance in the east of Mosul to attack Islamic State militants in Mosul, Iraq, Oct. 17, 2016.](https://gdb.voanews.com/77d6d402-7526-4b91-a191-6690407a5e09_w1024_q10_s.jpg)
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Peshmerga forces advance in the east of Mosul to attack Islamic State militants in Mosul, Iraq, Oct. 17, 2016.
![Smoke rises from Islamic state positions after an airstrike by coalition forces in Mosul, Iraq, Oct. 17, 2016.](https://gdb.voanews.com/411abdbe-df01-45d0-b4de-d78693dbc17e_w1024_q10_s.jpg)
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Smoke rises from Islamic state positions after an airstrike by coalition forces in Mosul, Iraq, Oct. 17, 2016.
![This photo released on his official Facebook page shows Iraqi Prime Minister Haider al-Abadi, center, surrounded by top military and police officers as he announces the start of the operation to liberate the northern city of Mosul from Islamic State milit](https://gdb.voanews.com/a0b57a73-c5a1-4045-9e4b-0c8d1e5ac5c4_w1024_q10_s.jpg)
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This photo released on his official Facebook page shows Iraqi Prime Minister Haider al-Abadi, center, surrounded by top military and police officers as he announces the start of the operation to liberate the northern city of Mosul from Islamic State milit
![Kurdish Peshmerga fighters stand on top of a military vehicle as they advance towards villages surrounding Mosul, in Khazer, about 30 kilometers (19 miles) east of Mosul, Iraq, Oct. 17, 2016.](https://gdb.voanews.com/11fe558b-2351-4f43-9ce5-8178b975ca58_w1024_q10_s.jpg)
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Kurdish Peshmerga fighters stand on top of a military vehicle as they advance towards villages surrounding Mosul, in Khazer, about 30 kilometers (19 miles) east of Mosul, Iraq, Oct. 17, 2016.