ATHENS (Reuters) - A Greek guerrilla group has claimed responsibility for a makeshift bomb blast in central Athens late on Wednesday that it said targeted a prosecutor and warned its next strike would not be limited to material damage.

The Conspiracy of Fire Cells group said the bombing was a show of support for their jailed members and other "political prisoners behind bars" in Greece and accused the targeted prosecutor of shelving cases to protect business interests.

"We chose a symbolic hit aiming only for material damages but in the future, the Conspiracy of Fire Cells will not be limited to that," the group said in a statement posted on the internet.

Police said they were examining the authenticity of the claim.

The urban guerillas claimed responsibility for a wave of parcel bombs sent to foreign embassies in Athens in 2010. They are on a U.S. blacklist of terror groups.

The late-night blast occurred in the Athens neighborhood of Exarhia, damaging the entrance of a building and shattering nearby shop windows.

The Cells initially specialized in arson attacks but turned to bombings in May 2009. In 2011, six of their members were sent to prison with sentences ranging from 11 to 37 years.

(Reporting by George Georgiopoulos; Editing by Tom Heneghan)