By Dominic Evans and Ahmed Rasheed
BAGHDAD (Reuters) - Western-backed Iraqi forces have begun shelling parts of west Mosul, residents said, in preparation for a new front against Islamic State seven weeks into a difficult campaign to drive the militants from the city.
Federal police forces, stationed a few miles (km) south of Mosul, on the west bank of the Tigris river that divides the city, have long said they aim to advance toward the airport on the southwestern edge.
Military commanders hope that by opening a second front within the city they can increase pressure on the few thousand jihadists who have deployed suicide bombers, snipers and militant cells against elite Iraqi troops in eastern districts.
Some 100,000 Iraqi soldiers, security forces, Kurdish peshmerga fighters and mainly Shi'ite paramilitary forces are participating in the assault that began on Oct. 17, with air and ground support from a U.S.-led international military coalition.
Mosul is the largest city under Islamic State control and driving the militants out would roll back the self-styled caliphate which it declared in Iraq and Syria 2014 after seizing large parts of both countries.
The campaign entered its eighth week on Monday but militants still control three-quarters of the city, where around 1 million residents are living under increasingly siege-like conditions as winter sets in.
Speaking by telephone from western neighborhoods, residents reported what they said was the first artillery or mortar bombardment of the area.
"About 10 mortar bombs fell on the neighborhood, coming from the south, as the Iraqi forces approached...during the past 24 hours," a resident of the Mosul al-Jadida district told Reuters late on Sunday. "It has sparked panic among civilians because this is the first time it has happened in our area."
He said the bombardment had led to a virtual curfew in the district, with people afraid to leave their homes.
"One of the mortar bombs exploded 100 meters from our house, killing three youths and wounding others," he said.
MILITANTS ON THE MOVE
In the adjacent neighborhood of Mansour, a resident said the bombardment was an ominous development. "We're worried there will be a repeat of the scenario in the eastern districts which have seen humanitarian disasters," he said.
An Iraqi police source, speaking from the front line south west of Mosul, said police rockets or mortars were not yet within range of the edge of the city.
But a military source said French artillery forces, who are supporting the police units, had been firing in the south. The U.S.-led air coalition has also conducted some air strikes.
Another Mosul resident said on Monday there had been "constant" air strikes against targets around the airport and in the Tel Roman district on the southwestern edge of the city.
Militants were reported to be on the move. People said they saw 40 or 50 pickup trucks with rocket launchers on top leaving Wadi Agab, an industrial area on the western limits of the city targeted by strikes, and moving to residential areas nearer the expected new front line.
A shopowner near the industrial area said he saw a long queue of pickups leaving the industrial area on Sunday. "This morning I saw more vehicles leaving. I counted at least 50 trucks," he said.
FIGHTING IN EAST MOSUL
The long-awaited attack from the south aims to relieve pressure on Iraqi Counter Terrorism Service (CTS) troops which have spearheaded the fighting in east Mosul for the last month and have come up against the militants' lethal defenses.
Officers say they are engaged in fierce urban warfare, facing hundreds of suicide car bombers, snipers and militants exploiting a network of tunnels underneath residential areas to launch deadly counter-attacks.
The presence of civilians throughout the city has also hampered their progress, they say, reducing options for air strikes and heavy weapons in the densely populated streets.
At current rates of progress, the campaign is set to last well into next year, raising fears among residents and aid groups of a humanitarian crisis, with possible food, fuel and water shortages in militant-held districts largely surrounded.
Iraqi commanders say they have killed at least 1,000 of the 5,000-6,000 Islamic State fighters they estimated were defending the city when the campaign was launched.
The military has not given figures for its own casualties. The United Nations said last week nearly 2,000 members of the Iraqi security forces had been killed across Iraq in November - a figure Baghdad says was based on unverified reports - and that more than 900 police and civilians had also been killed.
Iraqi commanders say they continue to make progress, and U.S. Defense Secretary Ash Carter said on Monday it was still possible that the city would be recaptured before President-elect Donald Trump takes office on Jan. 20.
Sabah al-Numani, spokesman for the elite Iraqi CTS units, said they pushed into the east Mosul district of Bareed early on Monday. "Our heroic forces are launching a street fight in al-Bareed since the early morning hours in a bid to control the district. Fighting is still continuing," he said.
The fighting in Bareed follows a series of counter attacks by Islamic State forces since Friday night in east Mosul, as well as to the south and west of the city.
The International Organisation for Migration says 81,000 people have been registered as displaced since the start of the 50-day-old campaign.
That figure does not include many thousands of people forced by the militants to accompany them as human shields as they retreated into the city last month, or others who have fled the fighting deeper into territory controlled by Islamic State.
The World Health Organisation said on Monday it had delivered medicines and medical supplies for 13,000 people in east Mosul.
(Additional reporting by Saif Hameed in Baghdad and Isabel Coles in Erbil; editing by Philippa Fletcher)