Explosions tore through the departure hall of Brussels airport on Tuesday morning killing up to 10 people and injuring 30 others and a second blast struck a metro station in the capital shortly afterwards, the Belgian public broadcaster RTBF said.
The Belga agency said shots were fired and there were shouts in Arabic shortly before the blasts at the airport. Pictures on social media showed smoke rising from the terminal building through shattered windows and passengers running away down a slipway, some still hauling their bags.
The blasts at the airport and metro station occurred four days after the arrest in Brussels of a suspected participant in November militant attacks in Paris that killed 130 people. Belgian police had been on alert for any reprisal action.
British Sky News television's Alex Rossi, at the airport, said he heard two "very, very loud explosions".
"I could feel the building move. There was also dust and smoke as well... I went towards where the explosion came from and there were people coming out looking very dazed and shocked."
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"The thinking here is that it is some kind of terrorist attack - that hasn't been verified by any of the authorities here at the airport."
RTBF said the metro station hit by the explosion was close to European Union institutions. Authorities closed all metro stations in Brussels, but there were no details immediately available of any casualties in this second incident of the day.
The European Commission has locked down its staff after the apparent attacks.
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