Meanwhile – Belgium closed metro, train, tram and bus services in the capital Brussels on Tuesday following bomb blasts in the airport and metro, the authorities said.

“Bus, tram and metro shut down,” the Brussels public transport operator STIB said in a message on Twitter. Major railway stations are also closed, the Brussels public prosecutor said separately.

A string of explosions rocked Brussels airport and a city metro station on Tuesday, killing at least 13 people, according to media reports, as Belgium raised its terror threat to the maximum level.

Two explosions targeted the main hall of Zaventem Airport at around 8:00 am (0700 GMT), with a third hitting the Maalbeek metro station, near the European Union’s main buildings, just as commuters were making their way to work in rush hour.