Soldiers of the Iraqi army enter Bartella village after they defeated the Islamic State militants in Bartella village, about 20 km east of Mosul, northern Iraq on Oct. 22, 2016.(Xinhua Photo)

MOSUL, Iraq, Oct. 31 (Xinhua) -- Iraqi security forces on Monday advanced closer to the fringes of the city of Mosul in the latest push to drive out Islamic State (IS) militants from their last major stronghold in Iraq.

After several hours of fierce fighting, the troops recaptured the villages of Bazwaya, Tubriq and Tahrawa, and are now just three km from the outskirts of Mosul, a source from the Joint Operations Command told Xinhua on condition of anonymity.

Earlier in the day, a military statement said the Iraqi army and counter-terrorism forces started the operation at 6:30 a.m. (0330 GMT), advancing in three routes toward the eastern side of the Tigris River, which bisects the city.

The Iraqi army has unleashed artillery and mortar fire on IS positions in the industrial area outside Mosul, as Iraqi and allied aircraft pound IS positions inside and outside the city, the source said.

During the past two weeks, Iraqi security forces had inched to the eastern fringes of Mosul, and were making progress on other routes around the city, preparing for a major battle to storm the city and drive out IS militants.

On Oct. 17, Abadi announced the start of a major offensive to retake Mosul, the country's second largest city.

Mosul, some 400 km north of the Iraqi capital of Baghdad, has been under IS control since June 2014, when Iraqi government forces abandoned their weapons and fled.