Two explosions have been reported at ‘American Airlines’ check-in desk at Zaventem airport in Brussels.
Images on social media from the scene showed smoke rising from one of the terminal buildings.
The Belgian broadcaster RTBF quoted a witness as saying there were people injured or unconscious in the departure area, opposite the Sheraton hotel.
The blasts come four days after the capture in Brussels of Salah Abdeslam, the main suspect in the Paris attacks in November.
Belgian media say the airport is being evacuated as flights and rail transport to the facility have been halted.
Medical sources report that ten people have died from both bombings with as many as 30 people reported injured as unconfirmed reports also allege that yet another bomb went off at a metro station in Brussels.