At least four hostages held in Syria by Islamic State militants, including US journalist James Foley, were waterboarded during their captivity, The Washington Post has reported.
The newspaper, citing people familiar with the treatment of Western hostages, said the Islamic State captors appeared to model the technique used by the CIA on three terrorism suspects captured after the 11 September attacks on the World Trade Center.
A source close to the family of a hostage held by Islamic State acknowledged to Reuters that hostages had been waterboarded, but gave no further details.
Waterboarding, a process characterised by Barack Obama and many other US politicians as torture, simulates drowning. Captives have water poured over their noses and mouths until they feel as if they are suffocating.
Three Americans and fewer than 10 other western hostages are still being held by the militant group, according to people familiar with the situation.
More than 150 Syrian soldiers were stripped and marched into the desert to be shot by Islamic State militants, activists have claimed.
A video has been posted to YouTube purporting to show the men, who are barefoot and in their underwear, being escorted into the desert.
It then goes black before revealing a similar number of men, also in their underwear, lying dead in the sand.
The video has yet to be verified but correspond to other reports from the region, and tie up with a statement and claims made via Twitter relating to the mass killing of troops captured in recent fighting for a string of military bases in north-eastern Syria.
There has been no immediate comment from the Syrian government.
The UN is "making every effort to secure the release" of 43 peacekeepers detained by an armed group near Al Quneitra in the Golan Heights.
A further 81 peacekeepers are "currently being restricted to their positions" near Ar Ruwayhinah and Burayqah, the UN said.
The nationalities of the peacekeepers, who were serving with the UN Disengagement Observer Force Zone (UNDOF), is not clear. As of 31st July, there were peacekeepers from Ireland, the Netherlands, Fiji, Nepal, India and the Philippines serving in the force.
Syrian jets shelled rebel positions near the Quneitra border crossing between Syria and the Israeli-occupied Golan Heights and fighting in the area is ongoing.
The United Nations has said that 43 of its peacekeepers in the Golan Heights have been detained today by an armed group in Syria.
It is working to secure their release.
A spokesman for UN Secretary-General Ban Ki-Moon has said that any violation of the ceasefire agreed today would be "utterly irresponsible".
He said the blockade of Gaza must end, and that the territory must be brought back under the control of one legitimate Palestinian government adhering to Palestine Liberation Organisation commitments.
"Israel's legitimate security concerns must be addressed," he added.
Three member of a UN peacekeeping helicopter crew that crashed in South Sudan have died, the UN said. One survivor is being treated.
The cause of the crash remains unclear.
The UN Mission in South Sudan has said that one of its helicopters has crashed close to the small town of Bentiu in Unity State.
UNMISS said it was "deeply concerned about fate of crew".
UNMISS deeply concerned about fate of crew, has dispatched a search & rescue team to site of incident.
The UN Human Rights Council is set to hold an emergency session on Wednesday on the situation in Gaza following a request by Egypt, the United Nations has announced.
Insurgents in northern Iraq have seized nuclear materials from Mosul University, according to a letter from an Iraqi ambassador to the United Nations.
The letter appealed for UN help to "stave off the threat of their use by terrorists in Iraq or abroad" after around 88 pounds of uranium compounds were apparently seized.
In a letter obtained by Reuters, Iraq's UN Ambassador Mohamed Ali Alhakim told Secretary-General Ban Ki-moon on July 8: "Terrorist groups have seized control of nuclear material at the sites that came out of the control of the state."
He added that the nuclear materials could "be used in manufacturing weapons of mass destruction" and warned they could also be smuggled out of Iraq.
The materials were not believed to be enriched uranium and therefore would be difficult to use in manufacturing a weapon of mass destruction, a US government source told the news agency.
Russia has called an emergency meeting of the United Nations' most powerful body, seeking an immediate halt to the deadly clashes in eastern Ukraine - after months of blocking any Security Council action.
Russian foreign minister Sergey Lavrov said Moscow now wanted Security Council action to end weeks of violence in Russian-speaking eastern Ukraine between government troops and pro-Russian insurgents, a move immediately denounced by the United States as "hypocritical".