Federal prosecutors said on Friday that they had charged a man detained in Brussels with terrorist murders and participation in the activities of a terrorist group.
Two other people picked up in the eastern town of Verviers on Thursday were released. Belgian broadcaster RTBF said they were the brother and father of the man charged.
A court also ordered on Friday that a suspect named as Ali O. and an unidentified person who was picked up on Monday morning be held in custody for a month.
Belgium is still hunting Brussels-based Salah Abdeslam, whose brother blew himself up in Paris and who called up a friend from Paris on the night of the attacks seeking a lift back to Brussels.
Belgium has charged the two men who went from Brussels to pick him up as well as Ali O., 31, who took Abdeslam to another part of the city after his arrival on November 14.
A 39-year-old Moroccan named Lazez A. has also been charged after police found two handguns and traces of blood in his car. Prosecutors have not given details about a fifth suspect.
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