An aid agency has warned of a "human catastrophe" unfolding in the Iraq city of Fallujah.
Jan Egeland, head of the Norwegian Refugee Council, said only one family had managed to escape the besieged town on Monday.
"Warring parties must guarantee civilians safe exit now, before it's too late and more lives are lost", Egeland said.
Egeland's comments come on the day Iraqi forces repelled a four-hour counterattack, a day after entering the southern part of the city.
He added a lack of food, medicine, safe drinking water and electricity is "pushing families to the brink of desperation".
It is estimated that 50,000 civilians are still inside Fallujah and humanitarian groups have renewed calls on both sides to open up safe corridors for non-combatants to flee.
This appears unlikely as IS and the Iraqi forces need to agree on a cessation of hostilities - whilst Iraqi authorities want to prevent IS fighters from escaping the city by mixing with the fleeing civilian population.
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