Thousands of refugees are pouring out of Fallujah through a safe exit corridor secured by the Iraqi army as the fight to retake the city from Islamic State extremists rages into its third week.
According to Lise Grande, the UN humanitarian coordinator for Iraq, 3,300 people fled Monday, joining another 4,000 who escaped during the weekend.
Thousands more are expected to make the journey in the coming days, overwhelming humanitarian efforts to help them.
Most of the civilians fleeing the fighting are going into 27 camps housing displaced people from other parts of Iraq's Anbar province.
"The problem is, the camps are full," Grande said.
There is a massive effort underway to catch up, with various U.N. agencies and non-governmental organizations working to build new camps, while providing food, safe drinking water, latrines, mobile clinics, and help for women who have suffered violence by IS extremists.
"We underestimated how difficult conditions were in Fallujah itself," Grande said, adding there were reports that "families have been brutalized, women have been brutalized, children have been brutalized."
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More refugees expected
According to the United Nations, 43,000 people have run away from the city, despite the dangers of roadside bombs or being killed by Islamic State fighters.
The sudden rush out came after Iraqi forces, working with local tribal fighters, opened one safe exit corridor for civilians. They are now fighting to open up a second.
Between 40,000 and 50,000 additional people could still be trapped in the city center, Grande told reporters in a live broadcast from Baghdad.
According to the Norwegian Refugee Council, some families have been trying to escape by leaving at night and making their way to the Euphrates River, some paying IS roughly $130 to allow them to take small boats across the water.
Families have lost children on the way, some have drowned on the river crossing, others have been executed by Islamic State. Many are facing starvation.
Nuriya is a refugee who managed to escape on a boat across the Euphrates.
"It was total chaos," she told the Norwegian Refugee Council. "When the boat I was on reached the middle of the river, I heard a lot of screams; another boat was sinking. People were shouting, ‘Save us, save us.’"
She said people jumped in to try to rescue those who were drowning, but came too late for her son's two daughters and young son.
"Their mother was holding onto two of them, one of them was still alive, the other was already dead, until she lost them," she said.
Humanitarian agencies are calling for more help from the international community.
"The needs are great, the resources are limited, and the time to meet their needs is limited because they have gone through an enormous time of deprivation before reaching here," said Bruno Geddo, the UNHCR representative in Iraq.
For those who escape, the UNHCR has said there are credible eyewitness reports that some men and boys are facing physical abuse by armed militias operating in support of the Iraqi security forces.
Those groups are "separating the men and teenage boys from the women and children, and detaining the males for ‘security screening,' which in some cases degenerates into physical violations and other forms of abuse, apparently in order to elicit forced confessions," said the U.N. High Commissioner for Human Rights Zeid Ra'ad al-Hussein.
"There are even allegations that some individuals have been summarily executed by these armed groups," al-Hussein said in a statement from Geneva last week.
The governor of Anbar province, where Fallujah is located, said Sunday that 49 displaced civilians who had reached areas controlled by the Shi'ite militia had been killed. Hundreds more were missing, Suhaib al-Rawi told reporters.
Some Sunni tribal fighters are battling alongside the Iraqi army and counterterrorism forces, as are a number of Shi'ite militia who operate under the umbrella name of Hashd al Shaabi.
Grande said 7,200 men and boys had been separated from their families to be screened. About 2,000 are still being held.
"There is a big backlog," Grande said.
Fallujah is a traditionally Sunni stronghold that has been under IS control for more than two years.
There have long been concerns the sectarian nature of the war against Islamic State extremists could be exacerbated by the presence of the Shi'ite militia.
Al-Hussein says Iraqi security forces have a legitimate interest in vetting those fleeing IS-controlled areas to ensure they don't pose a security threat, but he says that screening has to be done legally.