Four out of the 11 suspected members of far-right group Combat 18 Hellas were released on Friday after defending themselves before an investigating magistrate on charges of possession of fire arms and drugs.
The other seven suspects, who face more serious charges, including running a criminal organization and arson, are to face the same magistrate on Saturday.
The group is believed to be behind more than 30 attacks, chiefly targeting anarchist squats and Jewish memorials.
The four suspects who testified on Friday, one of whom is a minor, were questioned about the group’s activities even though they are not believed to have played an active role.
They were escorted away from the Athens court complex where they gave their testimonies under heavy police guard as a crowd of anarchists jeered them.