Two journalists at the prominent German news website Netzpolitik are under investigation for treason after publishing details about the planned expansion of the German Secret Service’s Internet surveillance program.

On Wednesday, the organization received a letter from the Federal Attorney General of Germany confirming ongoing investigations against reporters Markus Beckedahl, Andre Meister (pictured), and an “unknown source” for the articles, one of which was published in February and detailed a secret budget plan for surveillance activities, and another, from April, describing a new surveillance unit for monitoring social networking and online chats. Meister has characterized the plans as being part of Germany’s “post-Snowden” internet surveillance push.

Netzpolitik, which reports on politics and technology, learned within the last several weeks that Federal Attorney General of Germany was investigating the stories, but believed its sources were the target of the investigation rather than its journalists, Meister said in an interview. Only yesterday did it became clear that Meister and Beckedahl were also under investigation.

“This is a direct attack on freedom of the press, such as hasn’t been the case in around 50 years in Germany, since the ‘Spiegel scandal’ in 1962,'” Meister told The Intercept, citing an incident in which the German newsweekly Der Spiegel was searched and some of its journalists were arrested on treason accusations stemming from an article questioning the preparedness of West German armed forces.

“These charges are an intimidation against media and against potential sources — which are an integral part of investigative journalism,” he added. “The public needs whistleblowers to find out about what’s done in their name and with their money. So the original investigations against our sources were already a direct attack on freedom of press and freedom of information.”

The attorney general’s letter cites a section of the German penal code that states:

Whosoever … allows a state secret to come to the attention of an unauthorised person or to become known to the public in order to prejudice the Federal Republic of Germany or benefit a foreign power and thereby creates a danger of serious prejudice to the external security of the Federal Republic of Germany, shall be liable to imprisonment of not less than one year.

Meister railed against the implication that he or his publication have attacked the German state, saying that, as part of a “fourth pillar” in German society, their job is to “dig deep, investigate, and provide the public with information that has not previously been public … providing the public — and thus the sovereign — with information for public debate that’s integral for informed consent.”

“Germany won’t be invaded because of our reporting,” he added. “On the other hand, one could argue that the pervasive mass surveillance of the digital world is an attack on the basic freedoms of a free society. Without privacy, there can be no freedom of thought and freedom of association without a protected, un-invaded private space. We want to enable a public debate about these integral issues.”

The charges have generated significant attention in Germany. A public demonstration has been organized in support of Netzpolitik, and today they received high-level support when the Heiko Maas, the German Federal Minister of Justice and Consumer Protection, expressed doubts to the Attorney General that journalists intended to harm Germany or aid a foreign power.

Asked if Netzpolitik would continue to report using materials gained from whistleblowers, Meister replied, “That’s our job, so of course we will continue to report about publicly relevant information, which obviously includes information from whistleblowers from state and private entities. As a matter of fact, just [yesterday] we have exposed the new ‘cyber strategy’ of the German Federal Military ‘Bundeswehr’ about offensive cyber attacks.”

“If anything, all the support is showing that we must be doing the right thing, so we will continue what we do and maybe even step up the pace. … To paraphrase a Google engineer after yet another NSA leak: ‘Fuck those guys!'”