After the NSA whistle-blower lands in Moscow, the big question is: Where is he?

A plane took off from Moscow on Monday heading for Cuba, but the seat booked by US National Security Agency leaker Edward Snowden was empty, and there was no sign of him on board.

An Aeroflot representative who wouldn't give her name said that Snowden wasn't on flight SU150 to Havana. And reporters from The Associated Press on the flight couldn't find him.

The Interfax news agency also quoted an unidentified Russian security source in Moscow as saying that Snowden wasn't on the plane.

The airline said earlier Snowden registered for the flight using his US passport, which US officials say has been annulled.

Snowden arrived in Moscow on Sunday from Hong Kong, where he had been hiding for several weeks to evade US justice. Ecuador is considering Snowden's asylum application.

After spending a night in Moscow airport, Snowden had been expected to fly to Cuba and Venezuela en route to possible asylum in Ecuador.

'Strong objections'

The White House said on Monday that it expected the Russian government to send Snowden back to the US and lodged "strong objections" with Hong Kong and Beijing for letting him go.

Hong Kong Chief Executive Leung Chun-ying on Monday defended his government's decision to allow Snowden to leave the city.

Leung said he noted "expressions of displeasure" from some in the US, but told reporters that "the people of Hong Kong expect Hong Kong to uphold its own laws including the Basic Law".

Beijing on Monday backed Hong Kong's permission for Snowden's departure.

"Hong Kong is a society with rule of law. The central government always respects the local special administrative region government to follow the Basic Law and the principle of 'One Country, Two Systems'," Hua Chunying, Foreign Ministry spokeswoman, said during a regular news conference.

Meanwhile, a Russian official said on Monday that Washington has no right to demand Moscow arrest and extradite Snowden.

"The Americans can't demand anything. We can extradite him, or we can refuse to do that," Russian human rights ombudsman Vladimir Lukin told the Interfax news agency.

In hiding

Snowden had been in hiding for several weeks in Hong Kong. The United States formally sought his extradition from Hong Kong to face espionage charges but was rebuffed. Hong Kong officials said the US request did not fully comply with their laws.

Washington was in touch through diplomatic and law enforcement channels with countries that he could travel through or to, reminding them that Snowden is wanted on criminal charges, and reiterating Washington's position that he should only be permitted to travel back to the US, a State Department official said.

Still, the United States is likely to have problems interrupting Snowden's passage. It does not have an extradition treaty with Russia, but does with Cuba, Venezuela and Ecuador. Even with an extradition agreement though, any country could give Snowden a political exemption.

The likelihood that any of these countries would stop Snowden from traveling on to Ecuador seemed remote. While diplomatic tensions have thawed in recent years, Cuba and the US are hardly allies after a half-century of distrust. Another country that could see Snowden pass through, Venezuela, could prove difficult, as well. Former president Hugo Chavez was a sworn enemy of the US and his successor, Nicolas Maduro, earlier this year called US President Barack Obama "grand chief of devils". The two countries do not exchange ambassadors.

Snowden's options aren't numerous, said lawyer for WikiLeaks founder Julian Assange, Michael Ratner.

"You have to have a country that's going to stand up to the United States," Ratner said. "You're not talking about a huge range of countries here."

It also wasn't clear if Snowden has finished disclosing highly classified information.

China Daily-AP-AFP-Reuters

(China Daily 06/25/2013 page12)