ATHENS -- A group of inmates at Greece's Korydallos Prison, which is housing maximum security inmates, held a sit-in on Saturday to protest against the transfer of an inmate to another prison complex, Greek national news agency AMNA reported.

A representative of the Justice Ministry, who is in talks with the protestors, confirmed that there is "an issue" at Korydallos Prison in suburb of Piraeus port, but failed to elaborate.

The ministry underlined that all the keys of the cells are in the guards' possession.

In a post on an anarchist website, a group of self-claimed "political prisoners" including Dimitris Koufontinas, a leading "November 17" terrorist group member who is serving 11 life sentences for murder, demanded the stay of the anarchist prisoner to end the turmoil.