Isis (Daesh) militants inside Fallujah are demanding citizens who want to leave the Iraqi city pay 150,000 Iraqi Dinars ($130, £91) for safe passage. The Norwegian Refugee Council, which runs refugee camps near Fallujah to the west of Baghdad, has said arriving refugees reported the militants had been looking to extract the sums, while using the tens of thousands still trapped as human shields.

Since the start of the Iraqi government's offensive in Fallujah, which began in May, some 27,600 residents have fled the city, where Isis has ruled for over two years. Around 4,000 of them were able to flee after Iraqi government forces retook a key road into the city on 12 June.

A litany of atrocities – perpetrated by both sides – have emerged since Iraqi forces, supported by Shia militias, began their bloody advance into the city.

Aid agencies have warned that Fallujah residents, some of them children, risk being forced to fight for Isis as the militant group uses food to lure the starving civilians to enlist.

Residents from the city have drowned or been killed by Daesh snipers as they attempt leave Fallujah across the Euphrates. Footage has emerged of the inhabitants using improvised rafts in attempts to leave the city being. They were reported to have used refrigerators and cupboards to cross the river rather than face the IEDs left on other roads by the Islamic State.

The United Nations has warned Fallujah's 50,000 inhabitants are being used as human shields by Islamic State, as fighting continues.

At the same time, civilians caught up in the advance by Iraqi Army and so-called Popular Mobilisation Forces risk torture at the hands of pro-government Shia militia.

According to Yahya al-Muhamadi, an Anbar council member working with displaced civilians and quoted by the Associated Press , five of those detained died while in the group's custody.