HONG KONG (AP) — The journalist who exposed classified U.S. surveillance programs leaked by an American defense contractor said Tuesday that there will be more 'significant revelations' to come from the documents.

"We are going to have a lot more significant revelations that have not yet been heard over the next several weeks and months," said Glenn Greenwald of The Guardian.

Greenwald told The Associated Press the decision was being made on when to release the next story based on the information provided by Edward Snowden, a 29-year-old employee of government contractor Booz Allen Hamilton who has been accused by U.S. Senate intelligence chairwoman Sen. Dianne Feinstein of California of committing an "act of treason" that should be prosecuted.

Greenwald's reports last week exposed widespread U.S. government programs to collect telephone and Internet records.

"There are dozens of stories generated by the documents he provided, and we intend to pursue every last one of them," Greenwald said.

Snowden's whereabouts were not immediately known on Tuesday, although he was believed to be staying somewhere in Hong Kong.

No charges have been brought and no warrant has been issued for the arrest of Snowden.