Germany's federal prosecutors are investigating whether a website that covers digital rights issues committed an act of treason for reporting on plans to expand the country's domestic surveillance of online communication.
Netzpolitik.org says it received a letter from prosecutors Thursday announcing the probe against two of its journalists and an unidentified source.
The site published an article in February detailing how Germany's domestic intelligence agency wanted additional funds to increase its online surveillance programs.
In April it published a follow-up story about the spy agency's efforts to set up a special unit to monitor social networking websites.
Both articles were based on leaked secret documents.
It is rare for German prosecutors to investigate journalists for treason, which carries a sentence of one year to life imprisonment.
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Netzpolitik report: bit.ly/1IubiDN