Belgian police have arrested two men suspected of planning an attack in the country after houses were searched yesterday evening, according to federal prosecutors.
The pair, named as 33-year-old Nourredine H and his brother Hamza H, will appear before a judge later today to determine whether they should be held in custody beyond an initial 24 hours.
"Based on provisional results from the investigation, it appears that there were plans to carry out an attack somewhere in Belgium," the federal prosecution office said in a statement.
For the time being there was no connection with the attacks at Brussels airport and the metro on 22 March, in which 32 people were killed, the prosecution office said.
Police carried out seven house searches in the Mons region and a further search at a house in Liege.
No weapons or explosives were found.
Brussels, home to European Union institutions and the headquarters of NATO, and Belgium in general are on a security alert level of three out of a maximum of four, a "serious" status with a "possible and probable" threat.