What – and where – now for Mr WikiLeaks?

Human rights activists are scouring more than 250,000 US diplomatic cables posted online by WikiLeaks to make sure named informants and campaigners have not been put in danger.

When WikiLeaks put 251,287 US State Department cables online with no redactions on Thursday night, it left thousands of sources and activists wide open to reprisals. The cables, which are now being pored over by governments, journalists and citizens, continue to reveal global secrets, but their unedited format means they could also prove lethal for US diplomats' sources.

Mike Blakemore, media director at Amnesty International, said he was concerned about possible attacks. "We're going through files to check that our own staff and partners we work with are not at risk. In the past we've recognised the value of what WikiLeaks has done, as it has shone a light on human rights abuses, but we always said they should take every precaution to make sure people aren't at risk."

Australia's Attorney General, Robert McClelland, said on Friday that the website's founder, Julian Assange, could face prosecution. "I am aware of at least one cable in which an intelligence officer is purported to have been identified," he said. WikiLeaks said it would shortly be releasing a statement.

Mr Assange is currently on bail while the High Court deliberates on whether to extradite him to Sweden on sexual assault charges. The written verdict is expected early next month, when judges return from their summer break. But even if he is not extradited to Sweden, his visa in Britain will have expired by the time the verdict is handed down, and the question arises about where he will go next. He risks arrest in Australia and already faces legal action in the US, where a grand jury is deliberating whether to prosecute him for disseminating classified documents.

The previously unreported cables seen by The IoS show deep concerns within the Government over attempts to control the threat from "home-grown" terrorists – particularly from the Somali community. Whitehall officials warned US counterparts at a meeting two years ago of "the growing threat... from home-grown jihadists and radicalised British Somalis and Somali-Americans, particularly those who have travelled to Somalia or Pakistan for indoctrination and training".

Ahead of tomorrow's UN summit on a roadmap for Somalia's political future, cables from 2009 expose the fragility of the Western-backed transitional government. Diplomats briefed that the transitional government was a "shell for Western policy," able to exist only thanks to the presence of African Union troops. In a stark foretelling of the dire famine now faced by the country, cables warned two years ago that malnutrition levels would be "increasingly difficult to address".

A briefing for an FBI chief on the eve of a visit to Hosni Mubarak four years ago revealed the co-operation the US enjoyed from the then Egyptian leader, who was deposed earlier this year. The note urged John Pistole to push Egypt to "share with us fingerprint records of suspected terrorists, to enter into the FBI's global fingerprint database". It added: "This would greatly advance our practical law enforcement co-operation."

The confidential communications also revealed American criticism of European leaders – including the "disastrous" experiences of Gordon Brown. On the eve of the last election, the US embassy in London ruled out the prospect of Mr Brown stepping down, suggesting it was "unlikely any Labour politician with his or her eye on the future would want to take on the sinking ship that is the current Labour Party at this time".

The embassy also named a series of senior civil servants and politicians as the sources of confidential intelligence. Britain's ambassador to the Vatican was named as the source of a warning that Pope Benedict's call for Anglicans to convert to Catholicism – on the eve of his visit to the UK – had propelled relations between the churches into "their worst crisis in 150 years".

A diplomatic cable from 2008 claimed the Indian Prime Minister, Manmohan Singh, said he had reached an "understanding" on the disputed territory of Kashmir with the then President of Pakistan, Pervez Musharraf. Mr Singh said: "We had reached an understanding in back-channels, in which Musharraf had agreed to a non-territorial solution to Kashmir that included freedom of movement and trade." Another message last year claimed the Israeli army's advocate-general had described how the force had used an unmanned aircraft to kill 16 Palestinians at a Gaza mosque.

Another cable details William Hague's account of a 2009 visit to Cuba, during which he told the foreign minister that "people in Britain were more interested in shopping than ideology". He "appeared disdainful... and said one needed shopping only to buy food and a few good books". The cable from Richard LeBaron, deputy chief of mission at the London embassy, implied the US was concerned about Mr Hague's "sudden interest" in Cuba.

WikiLeaks blames the Guardian journalist David Leigh for the latest unedited release, because he published a password to encrypted files in a book he co-wrote with Luke Harding on WikiLeaks in February. It alleges it was through this password that outsiders were able to access and circulate the files – prompting WikiLeaks to do the same. Leigh said on Twitter that the allegations were a "venomous packs of lies" and "deranged nonsense from Assange".