BBC News with David Austin

President Obama has said Russia is responsible for the violence in eastern Ukraine. In a statement of the White House Mr Obama said the separatists there were trained, armed and funded by Russia. He said the fighting in Ukraine was not the result of a homegrown indigenous uprising but a deep Russian involvement.

"Russia has deliberately and repeatedly violated the sovereignty and territorial integrity of Ukraine. And the new images of Russian forces inside Ukraine make that plain for the world to see. This comes as Ukrainian forces are making progress against the separatists. And as a result of the actions Russia has already taken and the major sanctions we've imposed with our European and international partners, Russia is already more isolated than at any time since the end of the Cold War."

Earlier Nato said about 1,000 Russian soldiers were now operating in Ukraine fighting alongside the pro-Russian separatists. The United Nations Security Council also met in emergency session in New York to discuss the crisis in eastern Ukraine. The US ambassador to the UN accused Russia of lying about its role. Russia's representative to the UN Vitaly Churkin said the presence of Russian volunteers in Ukraine had never been denied, but he did not respond to the allegation that Russian soldiers were operating alongside separatists in the east. He urged the United States not to intervene.

"Stop interfering in the internal affairs of a sovereign state. Stop trying to undermine a regime with your might. Restrain your geopolitical ambition."

The jihadist group Islamic State has posted a video online which appears to show the beheading of a Kurdish fighter in the Iraqi city of Mosul, which the group captured in June. Our Arab affairs editor Sebastian Usher reports.

Entitled a Message in Blood, the latest video produced by the skilled propagandists of Islamic State is clearly aimed at the Kurds fighting them in northern Iraq. It parades a group of Kurdish men dressed in orange jumpsuits. Other footage shows the same men apparently being captured on the battlefield. One of the men is then shown kneeling with three masked militants behind him. The backdrop is the main mosque in Mosul, the northern Iraqi city seized by the jihadists in June. In a choreography of murder very similar to the killing of the US journalist James Foley, he is then beheaded with a knife.

Officials in Afghanistan have said one of the country's most important historical sites, the Jam Minaret, will collapse if it isn't repaired urgently. The 800-year-old structure, which is a Unesco World Heritage Site, stands beside a river in Ghor province, and its base was badly damaged in floods last year. The circular minaret - described by Unesco as a graceful, soaring structure - is famous for its elaborate brickwork. It's the second tallest brick minaret in the world.

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The United Nations says 43 peacekeepers from its force monitoring the buffer zone between Israel and Syria in the Golan heights have been detained by militants fighting the Syrian army. A UN spokesperson said that another 81 troops were being restricted to their positions.

West African health ministers meeting in Ghana have agreed that travel restrictions should be lifted on countries affected by the deadly Ebola outbreak. The ministers were reacting to advice from the World Health Organisation. It says the restrictions create food and supply shortages and harm efforts to contain the virus. It recommends that countries affected by Ebola should conduct exit screening.

Turkey's new President, the outgoing prime minister, Recep Tayyip Erdogan says he will make joining the European Union and building peace with the country's Kurdish population his priorities in office. He was speaking after being sworn in as the country's first elected head of state. This report from Mark Lowen in Ankara.

It was a triumphant moment for Turkey's most powerful politician in a generation - Recep Tayyip Erdogan sworn in as the country's first elected president, a previously ceremonial post. He's vowed to change the constitution to increase his powers, but that is to come. Today the focus was on his oath of office. He swore allegiance to Turkey's sovereignty and its founding principle of secularism. But that, say his critics, is what he no longer upholds.

People in eastern Sri Lanka have asked the government for permission to shoot monkeys because they have become a nuisance. The council leader of Kattankudi said the animals were entering houses and eating food. He said more than 70 people have been bitten by monkeys this year. One conservationist told the BBC that the monkeys would learn to hide from any guns.

Those are the latest stories from BBC News.