Turkish Airlines halted flights to several Iraqi cities on Monday due to the ongoing operation to retake Mosul from Daesh terrorists.The official Twitter account of the airline said in a tweet that the flights to Najaf, Sulaimaniya and Basra were temporarily suspended due to the Mosul offensive, however all Turkish Airlines flights scheduled to Irbil and Baghdad were to continue as usual.Peshmerga forces loyal to northern Iraq's semi-autonomous Kurdish region and Baghdad-controlled Iraqi army forces launched a battle to free Iraq's second-largest city of Mosul from Daesh.Peshmerga forces now stand just 7 kilometers (4 miles) east of Mosul, while Iraqi army forces have started penetrating the Al-Kuwer area southeast of the city, military sources said.In mid-2014, Daesh captured Mosul, Iraq's second largest city, before overrunning vast swathes of territory in the country's north and west.