Iraqi forces capture second Mosul bridge in advance on IS

US-backed Iraqi forces captured the second of Mosul's five bridges on Monday, giving a boost to their onslaught on Islamic State's remaining stronghold in the western part of the city.

All of Mosul's five bridges over the Tigris have been destroyed but their capture facilitates the movement of forces progressing alongside the river,which cuts Mosul in two.

The bridge seized, al-Hurriya, is the second after one located further south. Its capture shields the back of the forces advancing toward a nearby government buildings complex.

"We control the western end of the bridge," said a senior media officer with the rapid response unit of the Interior Ministry, which is leading the charge toward the complex.

Recapturing the site would help Iraqi forces attack the militants in the old city. It would also mark a symbolic step towards restoring state authority over Mosul, even though the buildings are destroyed and not being used by Islamic State.

The battle of Mosul, which started in October, will enter an more complicated phase in the densely populated old city.

Civilians have been displaced in greater numbers in the past days, as the fighting rages in the middle of residential neighborhoods where populations have already been suffering for months from food, water and electricity shortages.

In the coming hours our forces will raise the Iraqi flag over the governorate building

- Shaalan Ali Saleh of the federal police

Iraqi forces captured the eastern side of Mosul in January after 100 days of fighting and launched their attack on the districts that lie west of the Tigris on Feb. 19.

Defeating Islamic State in Mosul would crush the Iraqi wing of the caliphate declared by the group's leader, Abu Bakr al-Baghdadi, in 2014, over parts of Iraq and Syria.

Baghdadi, Islamic State's leader, proclaimed the caliphate from Mosul's grand Nouri mosque in the old city centre which is still under his followers' control.

"In the coming hours our forces will raise the Iraqi flag over the governorate building," the federal police's Shaalan Ali Saleh told the Reuters news agency.

The militants have barricaded streets with civilian vehicles and rigged them with explosives to hinder the advance of Iraqi forces were also met with sniper, machinegun and mortar fire, as well as explosives dropped from light drones.

Federal police units who also taking part in the offensive are using similar drones to hit the militants.

The Iraqi military believes several thousand militants, including many who traveled from Western and central Asian countries, are hunkered down among the remaining civilian population, which aid agencies estimated to number 750,000 in western Mosul at the start of the latest offensive.

The militants are using suicide car bombers, snipers and booby traps to counter the offensive waged by the 100,000-strong force of Iraqi troops, Kurdish peshmerga fighters and Iranian-trained Shi'ite Muslim paramilitary groups.

They were also reported to have fired rockets and mortar rounds filled with toxic agents from the western side of the city to the eastern, government-controlled side.

More than 40,000 fled their homes in the past week, bringing the total number of those of displaced since the start of the offensive to nearly 210,000, according to the United Nations.

Aid agencies have expressed concern that camps to accommodate people fleeing are nearly full.

The UN last month warned that more than 400,00 people, more than half the remaining population in western Mosul, could be displaced.