BBC News with Julie Candler

The US Secretary of State John Kerry has condemned what he described as Russia's act of aggression in Ukraine. He was speaking during a visit to Kiev. From where Sarah Rainsford reports.

As he laid flowers at the shrines of dozens killed in Kiev, John Kerry was met by a crowd calling for his country's help. That is what he came here to offer, moral and political support for the interim government, and the promise of financial and its technical aid to help stabilize the economy. But most of all, he brought a message for Moscow, there is no evidence at all, he insisted, that it claimed that its troops are protecting Russian speakers in Ukraine, accusing Moscow of hiding behind falsehood and intimidation. In the 21st century, John Kerry warned, you can't invade another country, and dictate your demands down the barrel of a gun.

John Kerry was echoed shortly after with by President Obama, who said the fact that Russian soldiers were active in Crimea, meant Russia was using illegal force to exert influence on a neighbouring country. The Russian President Vladimir Putin earlier described his country's intervention in Ukraine as a humanitarian mission. He denied that the armed forces around in Crimean military bases in Crimea were anything to do with the Kremlin. Mr. Putin said they were a local defence forces and the Russia took no part in training them. Steve Rosenberg reports from Moscow.

Vladimir Putin said Ukraine had witnessed an unconstitutional coup, an armed seize of power. He continued, he said to recognize Yanukovych as the country's legitimate president. President Putin believed that Viktor Yanukovych was toppled by a Western plot to install an anti-Russian government in Kiev. he likened American officials to people doing laboratorial experiments on rats.

The Organization for Security and Cooperation in Europe is sending a military observer mission to Ukraine. Officials said 15 monitors are being sent as Ukraine has requested. And they will attempt to travel to Crimea. Earlier, troops in Russian uniform and Ukrainian soldiers were involved in a tense confrontation at an air base in Crimea.

There has been further violation in northeastern Nigeria. As a senator from Borno state said 11 people were killed in an attack by Islamist militants on Monday night in the city of Maiduguri. A resident said at least 40 had died. Here's Will Ross.

It seems Islamist militant fighters in Nigeria had decided to carry out attacks on a daily basis. The latest place to be targeted was Jakana village in Borno state. The senator representing the area Ahmad Zannah said the suspected Islamist militants had warned of the attack and so many people had fled the village to hide. Senator Zannah said soldiers have responded and this prevented the entire village from being destroyed. On Monday he accused soldiers of fleeing when another village was attacked.

World News from the BBC

The United Nations drug control agency has criticized moves to legalize cannabis in Uruguay and some US states. The International Narcotics Control Board said the plans contravened UN conventions restricting drugs to medical and scientific use. The Board's president said any relaxation of cannabis laws posed a danger to public health and should be reversed.

The lawyer for a Tunisian man who was jailed for insulting Islam said he's been freed. Jabeur Mejri was sentenced in 2012 to 7.5 years in prison, for posting a cartoon of the Prophet Mohammed on his Facebook page. Two weeks ago, Tunisian media reported that he'd been given a presidential pardon.

The Italian government has ordered immediate measures to save the world heritage site of Pompeii. The Roman city buried by a volcanic eruption almost 2,000 years ago. The site has been damaged by heavy rain. Alan Johnston reports from Rome.

Over the weekend, two walls collapsed in Pompeii. One at the Temple of Venus and the other in an area of tombs. Then on Monday the wall of a Roman shop came crashing down. Heavy rains have been blamed for the damage. Pompeii is one of the world's greatest archeological treasures. And the latest reports of the cave-in collapse prompted international pressure for action. In response, the Italian government has ordered immediate measures to protect vulnerable areas of the site. Its maintainance budget has to be boosted by well over $2.5m, and extra staff will be deployed.

Pope Francis is allowing members of the public to visit the sumptuous gardens of his summer retreat outside Rome. The residence at Castel Gandolfo, well luxurious property on the site of a former Roman villa, has been owned by the Holy See since 1596. And covers an area larger than the Vatican city itself.

BBC News.