The whereabouts of a former CIA employee who leaked top-secret documents about U.S. surveillance programs remain unknown two days after he checked out of a Hong Kong hotel.

Edward Snowden arrived in Hong Kong on May 20. His identity as the source of the secret information was revealed on Sunday at his own request.

He was last seen Monday afternoon, when he left his chic Hong Kong hotel.

There were no clues Tuesday or Wednesday as to where he might be or whether he remained in the Chinese special autonomous region, which maintains a Western-style legal system and freedom of speech.

Hong Kong has an extradition agreement with the United States, but there are exceptions in cases of political persecution or where there are concerns over cruel or humiliating treatment.