ATHENS — A far-left militant group in Greece known for staging attacks on political and foreign diplomatic sites has claimed responsibility for a bombing near Athens last month outside the offices of a major broadcaster and newspaper publisher.

In a post on the anti-establishment website Athens Indymedia on Tuesday night, the Group of Popular Fighters claimed responsibility for the Dec. 17 bombing, which caused serious damage to the facade of the building but no injuries. Greek news outlets reported at the time that 10 kilograms, or 22 pounds, of explosives had been used.

In its statement, the militant group said it had targeted the broadcaster Skai and the newspaper Kathimerini, which are part of the same media group and are housed in the same building, because they were among outlets that “played a special role in preserving the rotten economic and political system” during the Greek debt crisis. For a decade, the country was required by international creditors to adopt austerity measures in return for bailouts.

The group also accused news outlets of promoting a capitalist agenda in Greece and of “terrorizing society that beyond the E.U. there is nothing but chaos and hell.” It appeared to be referring to the idea, widely supported in 2015, that a compromise with creditors in the European Union and the International Monetary Fund was required to allow Greece to remain in the eurozone.