Is there a new Edward Snowden? US intelligence chiefs suspect a fresh leak
Latest exposure of internal operations of a US government anti-terrorist programme suggests leaks continued after ex-NSA contractor fled to HK
The latest media revelations about the US intelligence community has convinced officials they have another leak to journalists.
The concerns came after The Intercept, a news site that has had access to documents from leaker Edward Snowden, published items about the scope of the United States terror watchlist.
The Intercept report was "obtained from a source in the intelligence community". Previously, it has not hidden Snowden as its source, suggesting the latest scoop came from someone else.
Officials are now considering whether to ask the justice department for a criminal investigation into the suspected leak of the classified counterterrorism document to the website. The Intercept document provided a statistical breakdown of the types of people whose names and personal information appeared on two government data networks listing people with supposed connections to militants, an official said.
News network CNN, naming only "US officials", reported that national security officers feared a second source leaking classified intelligence from within their ranks.
The document published by The Intercept on Tuesday was dated August last year, months after US spy agency contractor Snowden had fled the US after sending classified documents from inside the intelligence community to the media.
Snowden, who has worked closely with two founders of The Intercept, writer Glenn Greenwald and filmmaker Laura Poitras, left his post as a National Security Agency contractor in Hawaii in May last year. He is not known to have had access to any secret materials since then.
An official said, however, that the government was not certain if a second leaker existed.
The apparent leak involved information on the Terrorist Identities Datamart Environment database (TIDE) and the Terrorist Screening Database, according to the document.
The document posted by The Intercept, a multi-coloured graphic classified "secret", said 680,000 names were "watchlisted" in the Terrorist Screening Database, an unclassified data network which was used to draw up more selective government watch lists.
The database contained the names of about 25,000 Americans or legal residents.
It said 280,000 of the 680,000 people were described by the government as having "no recognised terrorist group affiliation". A similar number on the list had suspected connections to militant groups, including al-Qaeda, Hamas and Hezbollah, it said.
The graphic said the more selective lists included a "no fly" list totalling 47,000 people who were supposed to be banned from air travel and a further "selectee list" of 16,000 people who were supposed to get extra screening by security personnel before being allowed to board aircraft.
The graphic said the screening database was, in turn, extracted from TIDE, a larger, ultra-classified database which contained 320,000 more names than the unclassified one, as well as raw intelligence information excluded from the screening system.
Because the graphic carried a "secret" classification, an official said, the agency which generated it, The National Counterterrorism Centre, was obliged to consider submitting a referral to the Department of Justice, which could then decide if a criminal investigation should be opened into the leak.
Last month, The Intercept published a document on the criteria and procedures by which names were placed on terrorist watch list databases. That document was labeled "Unclassified/for official use only/sensitive security information".
Additional reporting by Agence France-Presse