Belgian authorities have raided dozens of homes and arrested 12 suspects in a major anti-terror investigation which they say required "immediate intervention".
The federal prosecutor's office said that homes and garages were searched in 16 municipalities, mostly in and around Brussels.
The statement said 40 people were taken in for questioning, of whom 12 were arrested. It said there were no major incidents during the raids.
The operation comes as Belgium is still under the second highest terror alert in the wake of the March 22 attacks on the Brussels subway and airport which left 32 people dead.
Authorities are also especially aware of security risks during the Euro 2016 championships in neighbouring France. Belgium are playing Ireland on Saturday afternoon and big gatherings to watch the game are planned across the nation.
The prosecutor's statement said that "the results of the investigation necessitated an immediate intervention", indicating a violent attack was planned in the near future.
The federal prosecutor's office did not link the raids to the March 22 attacks, even though an eighth suspect was arrested late on Friday.
The Belgian man, identified as Youssef EA, was charged with "participation in the activities of a terrorist group, terrorist murders and attempts to terrorist murders".
Belgian media also reported that four top ministers, including Prime Minister Charles Michel, have received special protection following unspecified threats.