A prosecutor on Thursday appealed a misdemeanor's court decision earlier this month to acquit anarchist Costas Sakkas over charges of violating his restricted-residence order.
Sakkas, 30, who is accused of being a member of the Conspiracy of the Cells of Fire urban guerrilla group, was arrested January 7 after spending the night at a house in Neo Psychico, northern Athens, instead of his family's residence in Piraeus.
On January 8, the court ruled that there had been no violation of his restriction order.
Sakkas had been arrested on December 4, 2010, outside an apartment in Nea Smyrni, southern Athens, where arms were being hidden.
He was granted conditional release in July after going on hunger strike to protest the fact that he was being held in detention for two-and-a-half years, when the maximum period for pretrial custody was 18 months.
He denies being a member of Conspiracy of the Cells of Fire