(This story was last updated at 5:17 p.m. ET)

Edward Snowden, the former NSA contractor accused of leaking classified surveillance information, has asked Ecuador for asylum, the country's foreign minister says.

Snowden left Hong Kong earlier Sunday bound for a "third country," the government in the Asian hub said. He later landed in Moscow.

Ecuadorian Foreign Minister Ricardo Patino Aroca, who is on an official visit to Vietnam, said:

Earlier, Russia's ITAR-Tass news agency quoted an unidentified official from Aeroflot as saying Snowden would fly to Moscow and from there to Cuba on Monday, with an ultimate destination of Caracas, Venezuela. The anti-secrecy group WikiLeaks also said it was giving Snowden legal counsel and had helped him leave Hong Kong.

The government of the Hong Kong Special Administrative Region, or HKSAR, said in a statement that Snowden departed the territory "on his own accord for a third country through a lawful and normal channel." It did not say what his destination was.

CNN had a camera trained on the arrival area in Moscow for the Aeroflot flight Snowden was believed to be on, but there was no sign of him. However, The New York Times reported that other passengers on the plane said a black car pulled up on the tarmac after the flight landed; Russia Today, Russia's English-language television station, later reported that the car belonged to the embassy of Ecuador.

On Saturday, the U.S. asked Hong Kong, a semi-autonomous Chinese territory, for Snowden's extradition after federal prosecutors filed a criminal complaint last week charging him with espionage, theft and conversion of government property in connection with leaks to The Guardian newspaper about secret U.S. electronic surveillance programs.

Despite the extradition request, the HKSAR government said that documents from the U.S. asking for a provisional arrest warrant "did not fully comply with the legal requirements under Hong Kong law."

Hong Kong said it had asked the United States to provide additional information, but "has yet to have sufficient information to process the request for provisional warrant of arrest, [so] there is no legal basis to restrict Mr. Snowden from leaving Hong Kong," according to the statement.

Hong Kong said it had informed the U.S. of Snowden's departure.

Justice Department spokeswoman Nanda Chitre confirmed that Hong Kong told the U.S. that Snowden "departed Hong Kong for a third country.

"We will continue to discuss this matter with Hong Kong and pursue relevant law enforcement cooperation with other countries where Mr. Snowden may be attempting to travel," Chitre said.

State Department spokeswoman Jen Psaki would not specifically confirm reports that Snowden's U.S. passport had been revoked, but said the practice was "consistent with U.S. regulations ... for persons with felony arrest warrants."

"Such revocation does not affect citizenship status," Psaki said. "Persons wanted on felony charges, such as Mr. Snowden, should not be allowed to proceed in any further international travel, other than is necessary to return him to the United States."

A State Department official said the U.S. has been in touch with countries in through which Snowden might transit or that could serve as "final destinations."

WikiLeaks — whose founder, Julian Assange has taken refuge in Ecuador's London embassy to avoid extradition to Sweden on sex crime allegations — said on its Twitter feed that it was assisting Snowden.

"Mr. Snowden is currently over Russian airspace accompanied by WikiLeaks legal advisors," it said in a statement issued shortly after Snowden's Aeroflot flight departed Hong Kong.

In a later statement, Wikileaks said Snowden "is bound for the Republic of Ecuador ... for the purposes of asylum."

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