The children are the most vulnerable among tens of thousands of civilians trapped by the fighting for control of the city west of Baghdad.
Backed by aerial support from the US-led coalition, and paramilitary forces — mainly made up of Shiite militias — Iraqi government troops more than a week ago launched a military operation to recapture Fallujah, which has been under control of the extremist group for more than two years.
As the battled unfolds — with Iraqi forces pushing into the city’s southern sections after securing surrounding towns and villages — more than 50,000 people are believed to be trapped inside the Sunni majority city, about 40 miles west of the capital.
Unicef estimated the number of children trapped with their families inside the city at about 20,000, warning that they face a dire humanitarian situation, as well as the risk of forced recruitment by the militants.
“Children who are forcibly recruited into the fighting see their lives and futures jeopardised, as they are forced to carry and use arms, fighting an adults’ war,” said Unicef in a statement.
It called on “all parties to protect children inside Fallujah” and to “provide safe passage to those wishing to leave the city”.
Fallujah was the first large city in Iraq to fall to IS and is the last major urban area controlled by the extremist group in western Iraq.
The Sunni-led militants still control the country’s second-largest city, Mosul, in the north, as well as smaller towns and patches of territory in the west and north.
The fight for Fallujah is expected to be protracted, as IS has had more than two years to dig in. Hidden bombs are believed to be strewn throughout the city, and the presence of trapped civilians will limit the use of supporting air strikes.
On the ground, Iraqi special forces continued to push into the city from its southern edge, but are facing tough resistance from IS.