BERLIN - Germany's foreign intelligence service BND long spied on journalists of the BBC, The New York Times, Reuters and other media, news weekly Der Spiegel reported Friday.

Media rights group Reporters Without Borders labelled the alleged surveillance "a monstrous attack on press freedom", voiced fears the eavesdropping was ongoing and said it was planning legal action, according to Der Spiegel.

The magazine, which has extensively worked with US fugitive intelligence contractor Edward Snowden and reported on US and German espionage scandals, only cited documents it had seen. It reported that the BND had listed at least 50 telephone and fax numbers and email addresses of journalists or newsrooms on its list of "selector" keywords for surveillance since 1999.

These included several dozen numbers of the British Broadcasting Corporation at its London headquarters and in Afghanistan, as well as of the BBC World Service, it said.

A number of The New York Times in Afghanistan was also on the list, as were mobile and satellite phone numbers of news agency Reuters in Afghanistan, Pakistan and Nigeria.

The BND declined to comment, Der Spiegel said in an early excerpt of an article to be published in full in its weekly edition which hits news stands Saturday.

A BBC spokeswoman said: "We are disappointed to hear these claims.

"The BBC's mission is to bring accurate news and information to people around the world and our journalists should be able to operate freely and safely, with full protection for their sources. "We call upon all governments to respect the operation of a free press."