At least 31 people have died and more than 270 have been injured after a series of explosions struck Brussels airport and the metro system in an apparently coordinated attack.
The departure area of Zaventem airport was targeted by two blasts shortly after 08:00 local time (07:00 GMT).
At 09:00 a third explosion hit the Maalbeek metro station, near to the EU institutions.
Belgian authorities have closed the entire Brussels metro system and raised the security alert to level 4, the highest grade
The airport has been closed and all flights diverted.
The European Commission has cancelled all meetings at EU institutions and told employees to stay indoors.
The attacks come four days after the suspected mastermind of the Paris attacks, Salah Abdeslam, was discovered hiding out in a suburb of the Belgian capital.
Details about the attack remain sparse, with unconfirmed reports of gunfire and shouts in Arabic before the two explosions in the airport.
It is unclear whether the blasts were planned as a single coordinated attack, or the result of lone wolves acting separately under loose instruction.
Belgian authorities opened an emergency number for those concerned about relatives: +32 2 506 711
The UK Foreign Office have also set up a helpline for anyone affected or concerned about family and friends: +44 207 008 0000