Four MPs from the far-right Golden Dawn party have been handcuffed and hustled into a court building in Athens to respond to charges of belonging to a criminal organisation.
The four are charged on evidence that links the party to a string of attacks, including the stabbing of leftist rapper Pavlos Fyssas who was ambushed on September 17 and died from his injuries.
Golden Dawn deny any link to the murder.
The magistrate will now decide if the suspects remain in detention until a trial date is set.
Party leader, Nikolaos Michaloliakos and his deputy Christos Pappas are due in court later this week.
As the Greek government crackdown on Golden Dawn gathers pace, details of the inner workings of the party are beginning to emerge, such as assault squads and military type training.
Searches of the homes of those arrested found Nazi memorabilia.
The operation against the party has been well planned. Local media report that police officers thought to be members of Golden Dawn were suspended ahead of the operation to detain the MPs to avoid tip-offs.