ATHENS: The head of Greece's extremist right-wing Golden Dawn party was jailed early Thursday, pending trial on charges of running a criminal organisation in an investigation into his party triggered by the killing of a left-wing rapper.

Nikos Michaloliakos, who is a sitting member of Parliament, was ordered remanded in custody in the early hours of Thursday morning, after overnight testimony that lasted for more than six hours.

Armed police led him away from the courthouse in handcuffs.

His wife and daughter, who are also party members, as well as other Golden Dawn members of Parliament, stood outside the building and shouted words of encouragement to him as he was led away.

''The ridiculous little men, they decided to jail the leader,'' said party lawmaker Michalis Arvanitis.

On Wednesday, the court ordered the release of three party lawmakers and the jailing of a fourth in the same case. All have denied the charges against them.

Michaloliakos and five of his party lawmakers were among 20 people arrested over the weekend in a crackdown against the Nazi-inspired party following the Sept 17 fatal stabbing of rap singer Pavlos Fyssas.

It is the first time since democracy was restored in Greece in 1974 after a military dictatorship that sitting members of parliament have been arrested and jailed.

The government, which has vowed to eradicate the group, has argued the party has been acting as a criminal organisation rather than a political party.

Golden Dawn, which the government has described as a ''Nazi creation,'' rose from the margins of Greece's political scene to become the third most popular party in Greece amid the country's severe financial crisis. It has long been blamed for a series of violent attacks, mostly against immigrants.

The party denies it is behind any violence.

Rights groups and medical charities have long warned of an increase in the viciousness and frequency of attacks attributed to Golden Dawn members or supporters.

Two men arrested in January for the fatal stabbing of a Pakistani migrant were believed to be supporters of the group.

But Fyssas' death was the most serious crime attributed directly to an alleged party member.