At least 26 people were killed in twin attacks on Brussels airport and a rush-hour metro train in the Belgian capital on Tuesday, triggering security alerts across western Europe and bringing some cross-border transport to a halt.
A witness said he heard shouts in Arabic shortly before two blasts struck a packed airport departure lounge at Brussels airport. The federal prosecutor said one of the blasts was probably triggered by a suicide bomber.
The Belgian health minister said 11 people were killed in the airport bombing and 81 wounded.
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 and combat troops on the streets had been on alert for any reprisal action but the attacks took place in crowded public areas where people and bags are not searched.
Video showed devastation in the hall with ceiling tiles and glass scattered across the floor. Some passengers emerged from the terminal with blood spattered over their clothes. Smoke rose from the building through shattered windows and passengers fled down a slipway, some still hauling their bags.
Many of the dead and wounded were badly injured in the legs, one airport worker told Reuters, suggesting at least one bomb in a bag.
Britain, Germany, France and the Netherlands, all wary of spillover from conflict in Syria, were among states announcing extra security measures.
All public transport in Brussels was shut down, as it was in London during 2005 Islamist militant attacks there that killed 52. Authorities appealed to citizens not to use overloaded telephone networks, extra troops were sent into the city and the Belgian Crisis Centre, clearly wary of a further incident, appealed to the population: "Stay where you are".
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 toward where the explosion came from and there were people coming out looking very dazed and shocked."
Alphonse Youla, 40, who works at the airport, told Reuters he heard a man shouting out in Arabic before the first explosion. "Then the glass ceiling of the airport collapsed."
"I helped carry out five people dead, their legs destroyed," he said, his hands covered in blood.
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