Belgian Prime Minister Charles Michel said the alarm had been raised “following information of a risk of a Paris-style attack by individuals with arms and explosives”.
Belgian capital Brussels has been placed under the highest level four on the government threat scale – and the public warned not to gather in large numbers – after a meeting of top ministers, police and security services.
The rest of the country remains on level three of a “possible or probable” attack – which was raised in the wake of the Paris terror attacks.