Students in Brussels have begun returning to class after a two-day shutdown over fears that a series of simultaneous attacks could be launched around the Belgian capital.

The Grand Palace, Brussels.

The Grand Palace, Brussels. Image by Hernán Piñera / CC BY-SA 2.0

Special measures are being taken at primary and secondary schools plus universities, with student movements limited around or outside school buildings during the day.

Underground transport in Brussels is also starting up again after a four-day closure. Sections of the main metro are in operation but services are not running to outlying suburbs.

Belgian authorities set the city on maximum alert overnight on Friday amid warnings of an imminent security threat. More than 1,000 security personnel and soldiers have been deployed.

(Press Association)