Brussels attack: 'The whole of Europe has been hit'

"Through the attacks in Brussels, the whole of Europe has been hit," Hollande said in a statement, urging the continent to take "vital steps in the face of the seriousness of the threat".

French Prime Minister Manuel Valls said: "We are at war. Over the past few months in Europe we have endured several acts of war."

France, which neighbours Belgium to the south, was hit by two major terror attacks in 2015 and several of the jihadists behind them came from Brussels.

Also read: WATCH: Brussels airport hit by two explosions 

Attacks on November 13 in Paris claimed 130 lives, 10 months after attacks on the satirical newspaper Charlie Hebdo and a Jewish supermarket left 17 dead.

In an emergency cabinet meeting in London, Cameron has  called on Europe to stand together against the terror threat.

While, Belgian Prime Minister Charles Michel said the "blind, violent and cowardly" attacks on Brussels airport and the metro system were a "black day" for the country on national television.

Earlier, it was announced that Paris was deploying 1600 additional police to border crossings and air, sea and rail infrastructure after the Brussels attacks.

Germany, the UK and the Netherlands also announced stepped up security measures at borders, airports and rail stations.

Is there a South African in or near Brussels that you know? Email us [email protected].