BAGHDAD, Sept. 4 (Xinhua) -- A prominent leader of Islamic State (IS) group and four extremist militants were killed Sunday in a U.S.-led coalition airstrike near the IS stronghold of Mosul in northern Iraq, a security source said.
The airstrike destroyed four IS positions near the newly-freed town of Qayyara, some 50 km south of Mosul.
The prominent leader of IS, among the five killed, was said to be close to the top IS leader Abu Bakr al-Baghdadi, a security source on condition of anonymity told Xinhua citing an intelligence report.
The source didn't give the name of the prominent leader, adding that there were six other IS militants injured in the airstrike.
On August 25, Iraqi Prime Minister Haider al-Abadi declared the liberation of Qayyara after defeating the extremist militants.
Regaining control of the town and the airbase would help government forces free Iraq's last major IS stronghold in Mosul, which is located some 400 km north of the Iraqi capital of Baghdad.
Meanwhile, Iraqi aircrafts dropped leaflets over the besieged town of Shirqat, some 280 km north of Baghdad, and the nearby village of Zuwiyah, telling the residents to leave their homes immediately for secure places.
The residents, otherwise, must stay away from the positions of IS militants which will be targets of the Iraqi aircrafts, a statement issued by the Iraqi Joint Operations Command said.
Residents in Shirqat and other besieged cities and towns were prevented from leaving by IS militants who used them as human shields during armed military attacks.
However, the siege upon Shirqat imposed by security forces has drove most extremist militants to the IS major stronghold in Mosul.
The escape of IS militants weakened their grip on the town, enabling some of the residents to leave their homes, where long-term repeated power blackouts, acute food shortages, scarce drinking water and lack of medicine prevailed.
The security forces and allied paramilitary units known as Hashd Shaabi have been preparing for an operation to free the towns of Shirqat and nearby Hawijah as part of their major offensive towards liberating Mosul, the capital of Iraq's northern province of Nineveh, from the extremist militants.
Iraq has witnessed increased violence since the IS took over parts of its northern and western regions in June 2014.