LONDON — GCHQ harvested emails to and from some of the biggest media organisations on both sides of the Atlantic, according to a new Guardian report.

Emails from the BBC, Reuters, the Guardian, Le Monde, the Sun, the New York Times and the Washington Post were saved onto the intelligence agency's servers as part of bulk surveillance of electronic communications, analysis of documents released by Edward Snowden has revealed.

While some of the emails were mass-produced PR messages, many included conversations between reporters and editors discussing stories. It's not known if certain journalists were targeted, but other documents released by Snowden show that investigative journalists were listed alongside terrorists and hackers as a threat.

The emails were among 70,000 that one of GCHQ's fibre-optic taps scooped up within 10 minutes in November 2008, and are thought to have been captured by a tool designed to strip out irrelevant data.

A spokesman for GCHQ said the agency don't comment on intelligence matters, but added:

"All of GCHQ’s work is carried out in accordance with a strict legal and policy framework, which ensures that our activities are authorised, necessary and proportionate, and that there is rigorous oversight, including from the secretary of state, the interception and intelligence services commissioners and the parliamentary intelligence and security committee."

“All our operational processes rigorously support this position. In addition, the UK’s interception regime is entirely compatible with the European convention on human rights.”

One of the leaked documents, intended for army intelligence workers, said journalists and reporters were a potential threat to security.

“Of specific concern are ‘investigative journalists’ who specialise in defence-related exposés either for profit or what they deem to be of the public interest," the Guardian reports it as saying.

“All classes of journalists and reporters may try either a formal approach or an informal approach, possibly with off-duty personnel, in their attempts to gain official information to which they are not entitled.”

British Prime Minister David Cameron reiterated his pledge to increase surveillance powers last week, promising that conservatives will introduce a controversial data bill that will become known as the "snoopers' charter" if the party is elected in May's general election.

Meanwhile, the Society of Editors and Press Gazette drafted a letter, signed by more than 100 editors, to protest at police spying on journalists' phone records. It also voices concern that the draft code of practice from the Regulation of Investigatory Powers Act (RIPA) puts journalists' sources at risk. RIPA has been used to access journalists' communications without a warrant.