In a statement posted online on Sunday, the Hong Kong government confirmed that Snowden "left Hong Kong today on his own accord for a third country through a lawful and normal channel" and that it had informed the US of Snowden's departure.

Multiple reports said Snowden had left Hong Kong on a commercial flight, bound for Moscow. Russia's Interfax news agency, quoting an unidentified source at the Aeroflot airline, reported that there was a ticket in Snowden's name for a flight on Monday to Cuba, from where he was to fly to the Venezuelan capital, Caracas.

The WikiLeaks website has tweeted: "WikiLeaks has assisted Mr. Snowden's political asylum in a democratic country, travel papers ans [sic] safe exit from Hong Kong." It said Snowden was accompanied by legal advisors from WikiLeaks.

The former US National Security Agency contractor allegedly revealed the existence of the spy program Prism, which surveils phone and online activity.

A day after making public espionage charges filed against Snowden, US officials confirmed they had asked authorities in Hong Kong for his extradition. The 30-year-old is believed to have fled there in early June.

In Sunday's statement, the Hong Kong government announced that because the US request did not fully comply with Hong Kong law, it had asked for more information to analyze whether the request could be fulfilled.

On Friday, US prosecutors published the criminal complaint against Snowden, dated June 14. The charges were filed in the eastern district of the US state of Virginia, where his former employer, Booz Allen Hamilton, is based.

Snowden faces charges that could lead to a maximum sentence of 10 years in prison: unauthorized communication of national defense information, willful communication of classified information and theft of government property. The first two charges fall under the Espionage Act.

jr/mkg (Reuters, AFP, dpa, AP)