A court has convicted nine Muslims of belonging to a terrorist group and planning to attack Dutch politicians.
Mohammed Bouyeri is already serving the maximum prison term
Two men in the so-called Hofstad group were jailed for 15 and 13 years for using a hand grenade against police.
The court did not pass a jail term on the group's leader, Mohammed Bouyeri, as he is already serving life in prison for murdering film-maker Theo van Gogh.
The trial has been treated as a test of the Netherlands' tough new anti-terror legislation.
The new laws enable the Dutch government to prosecute people suspected of having the intention to commit terrorist acts.
Prosecutors had called for members of the Hofstad group to be jailed for up to 20 years, accusing them of inciting hatred of non-Muslims.
Five suspects in the trial were acquitted by the court, which ruled there was not enough evidence to show they were involved in planning terrorism.
Jason Walters, the son of a US citizen, received the heaviest sentence of 15 years, while Ismael Aknikh was given a 13-year jail term.
Both men were alleged to have worked together during a confrontation with police in November 2004, in which a hand grenade was thrown, injuring five officers.
None of the other accused was found to have carried out any terrorist acts. They received sentences ranging from one to five years.
The complex legal ruling, which took five hours to deliver, said most of the accused were guilty of promoting a violent ideology.
"Anyone who preaches hate and violence lays the basis for committing crimes directed at instilling fear among the people and destroying Dutch democracy," the ruling said.
"Threatening terrorist crimes strikes public order at its heart."
The judge said Bouyeri, although convicted of leading the group, could not be punished further as he was already serving life for Mr Van Gogh's murder.
Mr Van Gogh, whose best-known film attacked the treatment of women in Muslim societies, was stabbed to death in an Amsterdam street in November 2004.