MOSUL, Iraq, Sept. 28 (Xinhua) -- Islamic State (IS) militants on Wednesday set fire to three oil wells near the town of Qayyara, which Iraqi forces freed from the IS late last month in south Mosul, a local official said.
"Daesh terrorist group (IS group) planted bombs in three oil wells of Najma oilfield, which is still under IS control, and blew them up in the early morning," Salih Hassan al-Jubouri, the mayor of Qayyara, some 55 km south of Mosul, told Xinhua.
The blasts ignited enormous fires in Najma oilfield, just north of the town of Qayyara, sending black smoke above the town and nearby villages, Jubouri said.
Earlier in the month, the Iraqi oil ministry said fires were put out at at six oil wells in and around Qayyara.
The fires were set by extremist militants before they fled Qayyara when security forces advanced on the town.
The ministry said several other oil wells were still on fire but they are outside the control of the security forces and will be extinguished as soon as the troops regain control.
On Aug. 25, Iraqi security forces freed Qayyara, a strategic town supposed to be used as a staging ground for a major offensive to liberate the last major IS stronghold in Mosul, some 400 km north of the Iraqi capital of Baghdad.
Mosul, the second largest city in Iraq, has been under IS control since June 2014, when Iraqi government forces abandoned their weapons and fled, enabling IS militants to take control of parts of Iraq's northern and western regions.