Iraqi security forces have begun the second phase of their offensive against Islamic State militants in Mosul, pushing from three directions into eastern districts where the battle has been deadlocked for nearly a month.

Since the offensive to capture Mosul began 10 weeks ago, US-backed forces have retaken a quarter of the jihadists’ last major stronghold in Iraq in the biggest ground operation there since the 2003 US-led invasion that toppled Saddam Hussein.

More than 5,000 soldiers and federal police troops, redeployed from Mosul’s southern outskirts, entered half a dozen southeastern districts, while counter-terrorism forces advanced in al-Quds and Karama districts after reinforcements arrived.

Other soldiers pushed simultaneously towards the city’s northern limits. US military advisers were seen watching operations as coalition aircraft circled overhead.

Smoke rises from clashes with Islamic State militants, north of Mosul, Iraq. (Photo: Reuters)

Iraqi forces have taken around half of the eastern side of Mosul, which is bisected by the Tigris river, but have yet to enter the western side, where 2,000-year-old markets and narrow alleyways are likely to complicate any advance.

The fall of Mosul would probably spell the end for Islamic State’s ambition to rule over millions of people in a self-styled caliphate, although the militants would still be capable of waging a traditional insurgency in Iraq, and plotting or inspiring attacks on the West.

A US-led coalition backing the Iraqis said the operation had opened two new fronts inside Mosul and limited Islamic State’s ability to raise fighter numbers, move them or resupply.

The US military later said a coalition air strike that hit a van in the parking lot of a hospital compound on Thursday (local time) may have killed civilians, highlighting the challenge of targeting an enemy embedded within the civilian population.

– Reuters