A journalist who helped US whistle-blower Edward Snowden disclose top-secret details of an internet surveillance programme, angering the Obama administration, said yesterday there were more secrets to expose. "We are working on stories [...] that we think are very valuable for the public to know that don't in any way harm national security but that shine a light on this extremely secretive though momentous agency," Glenn Greenwald told CNN, referring to the National Security Agency, which runs the programme Snowden has exposed. Greenwald, a columnist with British newspaper The Guardian , and Washington-based colleague Ewen MacAskill, interviewed Snowden in Hong Kong before the the 29-year-old checked out of his Tsim Sha Tsui hotel at the weekend. McAskill told CNN that Snowden was still in Hong Kong, but did not provide any further details of his whereabouts. "I probably suspect there will be a long drawn-out legal process here in Hong Kong. I'd imagine there's now going to be a real battle between Washington and Beijing and civil rights groups as to his future." Snowden's latest employer, Booz Allen Hamilton, a government contractor, said yesterday it had fired him "for violations of the firm's code of ethics and firm policy". It said he had earned a salary of US$122,000 a year. The company called Snowden's actions shocking and said he had been a Booz Allen employee for less than three months. The Obama's administration is weighing whether to charge Booz Allen with leaking classified surveillance secrets while it defends the broad US spy programme that it says keeps America safe from terrorists. Snowden previously worked for the CIA and likely obtained his clearance there. But like others who leave the government to join private contractors, he was able to keep his clearance. In response to inquiries from the South China Morning Post , the UN High Commisioner for Refugees' office in Hong Kong yesterday would not confirm whether it had received a refugee status application from Snowden, saying it would not comment on individual cases. Many in Washington are baying for Snowden's blood after he leaked details of the NSA's worldwide surveillance programme, while some social media commentators in China queried his choice of destination. Obama's spy chief, Director of National Intelligence James Clapper, described Snowden's leaks as gravely damaging to US security, and referred the matter to the Justice Department, which has launched an investigation. Others, such as WikiLeaks founder Julian Assange, called Snowden a "hero" defending personal liberty. A petition to pardon Snowden had attracted more than 30,000 electronic signatures a day after it was posted on the White House website. Snowden flew to Hong Kong last month after copying - at the NSA's office in Hawaii - the documents he intended to disclose. For now, Snowden has a 90-day visa which has about two more months to run. He could seek an extension, with Hong Kong having the right of refusal. Legal sources in Hong Kong said Snowden could seek representation by lawyers in the city, including the most prominent, Philip Dykes and Mark Daly. Dykes, who has worked on extradition cases, declined to confirm or deny he had been approached by Snowden. Daly, speaking from Geneva, said he was not aware of any approach from Snowden, but said he would be willing to represent him if asked. As things stand now, there is nothing to prevent Snowden from travelling to a destination of his choice. One of the Asian countries without an American treaty is China, though there is no guarantee Beijing would want to risk a confrontation with the US by taking Snowden in. Snowden might also consider Iceland or Russia. According to the Kommersant Daily , Moscow has said it might provide asylum. Agence France-Presse, Associated Press, Reuters