A demining expert from the Iraqi army searches for booby-trapped buildings in eastern Mosul on January 16, 2017, during an ongoing military operation against Islamic State (IS) group jihadists. (AFP/Xinhua)

MOSUL, Iraq, Jan. 20 (Xinhua) -- Iraqi security forces on Friday fought fierce battles to drive out the militants of the extremist Islamic State (IS) group from their last strongholds in the northern outskirts of the city of Mosul, the Iraqi military said.

The army soldiers, backed by Iraqi and U.S.-led coalition aircraft, freed part of al-Arabi neighborhood after heavy clashes with IS militants and raised the Iraqi flags on some of its buildings, leaving many IS militants killed and destroying a booby-trapped vehicle and a vehicle carrying heavy machine gun, the Iraqi Joint Operations Command (JOC) said in a statement.

Also in the day, the soldiers attacked a pharmaceutical plant and a commercial area, just north of Mosul, and recaptured them, leaving many IS militants killed, the statement said.

In central Mosul, the commandos of the Counter-Terrorism Service (CTS) launched an operations to clear the neighborhoods and areas freed recently from IS militants after the elite troops fulfilled their mission by recapturing the whole central part of the eastern side of the city, locally known as the left bank the Tigris River which bisects Mosul, according to the statement.

In addition, the soldiers made a new push into the last IS-held outskirts of al-Rashidiyah in the northern part of the eastern side of Mosul, sparking heavy clashes with IS defensive lines, the army Colonel Raad al-Aleiwi told Xinhua by telephone.

The commander of the elite Counter-Terrorism Service (CTS) forces said on Wednesday that CTS troops are now in full control of the main part of the eastern side of Mosul.

"CTS forces have completely retaken control of the eastern side of Mosul," Lt. Gen. Talib Shghati told reporters.

"The only neighborhoods left in Mosul are in the northern part of the city which the army units are fighting to liberate soon," Shghati said, adding that Mosul's five bridges over the Tigris river are all under security forces' control.

He said CTS troops have so far killed 3,300 IS militants and destroyed 300 car bombs in the Mosul battles.

Prime Minister Haider al-Abadi announced the start of a major offensive to retake Mosul, the country's second largest city, on Oct. 17.

The second phase of the offensive, to free the eastern bank of Mosul, began on Dec. 29.

Battles in Mosul decreased in December when extremist militants started using civilians as human shields, resorted to suicide car bombings and mortar and sniper attacks.

Mosul, 400 km north of the Iraqi capital of Baghdad, has been under IS control since June 2014, when Iraqi government forces abandoned their posts and fled, enabling IS militants to gain control of parts of Iraq's northern and western regions.