Seven people are going on trial in Belgium accused of being part of a group linked to Islamist militants who attacked Paris and Brussels.
Police broke up the cell when they raided a house in Verviers in eastern Belgium in January 2015.
Although 16 suspects have been charged in connection with the cell, nine of them are on the run.
Prosecutors believe the group was run by Abdelhamid Abaaoud, a ringleader of the 13 November attacks in Paris.
He was killed in a shootout in Paris days after the gun and bomb attacks in which 130 people were murdered.
Among those due to appear in court on Monday is Marouane El Bali, 26, who was arrested in the 15 January police raid in Verviers, in which two other suspects were killed.
Security was tight for the court appearance in Brussels.
At the time of the raid, prosecutors said the Verviers group had returned from fighting in Syria and were poised to carry out an attack. Police said a cache of explosives and weapons was found.
The raid came a week after jihadists attacked the offices of satirical magazine Charlie Hebdo in Paris, killing 12 people.
Belgian prosecutors say the cell had been planning an attack on police but a French special operations commander told media that they had intended to kidnap and murder a high-ranking Belgian official.
Police believe Abdelhamid Abaaoud had been directing the Verviers cell by telephone from Greece.
The trial is expected to last for three weeks.