NSA Whistleblower Snowden Not Welcome In UK The UK Government has urged airlines worldwide not to allow ex-CIA employee Edward Snowden, who leaked details of a secret US internet surveillance programme, to board flights to Britain. The alert, dated Monday on a Home Office letterhead, said carriers should prevent the former US intelligence contractor boarding UK-bound flights because "the individual is highly likely to be refused entry to the UK." Mr Snowden, an American citizen who leaked top-secret information about the controversial US Prism programme, has not been seen since he checked out of a Hong Kong hotel on Monday. He has admitted to giving details of the monitoring of phone calls and internet data, from companies such as Google and Facebook, to The Guardian and Washington Post. The Associated Press news agency reported seeing a photograph of the Home Office document taken on Friday at a Thai airport. It said a British diplomat confirmed that the document was genuine and had been sent out to airlines across the globe, and that a Thai airline also confirmed the alert had been issued. A redacted image of the leaked Home Office document The official, speaking on condition of anonymity, reportedly told AP that any carrier that brought Mr Snowden would be liable to be fined £2,000, adding that he would likely have been deemed by the Home Office to be detrimental to the "public good." The alert was issued by the Risk and Liaison Overseas Network, which is part of the UK Border Agency and has staff in several countries identified as major transit points for inadequately documented passengers. The document titled "RALON Carrier Alert 15/13" included a photograph of Mr Snowden, his date of birth and passport number. It said: "If this individual attempts to travel the UK: Carriers should deny boarding." It warned carriers may "be liable to costs relating to the individual's detention and removal" should they allow him to travel. The Home Office told Sky News that is was "not going to comment on individual cases." The National Security Agency headquarters in Fort Meade, Maryland Based on the information leaked by Mr Snowden, The Guardian and The Washington Post disclosed the existence of the Prism system - set up by America's National Security Agency (NSA) to track customer data directly from ISP servers to fight the threat of terrorism. The US has launched a criminal investigation to prosecute Mr Snowden for lifting and exposing the classified material. FBI Director Robert Mueller told the US House Committee on the Judiciary on Thursday that "all necessary steps" would be taken to hold Mr Snowden responsible for the leaks. "These disclosures have caused significant harm to out nation and to our safety," he said. As to the individual who has admitted to making these disclosures, he is the subject of an ongoing criminal investigation. Mr Snowden, who revealed himself as the source of the leaks on Sunday, has yet to be charged with any crime and no warrants have been issued for his arrest.