Iraqi forces began storming Daish-held Old City of Mosul on Sunday, an assault they hope will be the last in the eight-month campaign to seize the militants’ stronghold.
The historic district is the last still under control of the radicals in the city which used to be their capital in Iraq.
It is a densely-populated maze of narrow alleyways where fighting is often conducted house by house.
About 100,000 civilians remain trapped there in harrowing conditions, with little food, water and medicine and limited access to hospitals, according to the United Nations.
“This will be a terrifying time for around 100,000 people still trapped in Mosul’s Old City … now at risk of getting caught up in the fierce street fighting to come,” the International Rescue Committee (IRC) said in a statement.
“This is the final chapter” in the offensive to take Mosul, said Lieutenant General Abdul Ghani Al Assadi, commander of the Counter Terrorism Service (CTS) elite units spearheading the assault.
A US-led international coalition is providing air and ground support to the campaign. The Iraqi government initially hoped to take Mosul by the end of 2016, but the campaign took longer as militants dug in the middle of civilians to fight back.
Daish is also using suicide car and motorbike bombs, booby traps and sniper and mortar fire against the troops.
“The buildings of the old town are particularly vulnerable to collapse even if they aren’t directly targeted, which could lead to even more civilian deaths than the hundreds killed so far in air strikes across the rest of the city,” the IRC said.
“We are trying to be very careful, using only light and medium weapons … to avoid casualties among civilians,” CTS commander Major General Maan Saadi said.