Iraqi Sunni Arabs 'trapped in no-man's land between IS and Kurds'
The UN is increasingly concerned about 559 Sunni Arab Iraqis stuck in no-man's land between Islamic State (IS) militants and Kurdish forces.
The UN High Commissioner for Human Rights said they had spent three months living in deteriorating conditions near the town of Sinjar.
Since 4 February, they have been unable to access food and drinking water.
Two children and two women are believed to have died due to the cold weather, and IS has shelled them three times.
A spokesman for the Office of the High Commissioner on Human Rights Rupert Colville said the so-called IS had apparently threatened them with further attacks unless they agreed to relocate to territory controlled by the jihadist group.
He urged the Kurdistan Regional Government to "act as quickly as possible to ensure the safety, protection and access to basic humanitarian assistance for this group of extremely vulnerable people".
See where IS have made territorial gains and losses, Jan-Dec 2015
If the Kurdish authorities had security concerns about the group, they should vet people "on an individual basis in a safe location, in full transparency and in accordance with the law", Mr Colville added.
He did not say where the stranded people were from, but Kurdish forces are reported to have expelled dozens of families whose male relatives were suspected of having fought for or aided IS fighters.
The Kurds, backed by US-led coalition air strikes, recaptured Sinjar in November, 15 months after IS militants overran the north-western town and killed or enslaved thousands of members of the Yazidi religious minority who lived there.
Last month, the UNHCR said it had received reports of increasing human rights violations and abuses committed against Sunni Arab communities in parts of Iraq reclaimed from IS fighters, including looting and destruction of property, forced evictions, abductions, illegal detention and extrajudicial killings.
Sunni Arabs had also faced increasing discrimination, harassment and violence from other ethnic and religious groups who accuse them of supporting IS militants, it added.