Belgium's Tihange nuclear power plant has been evacuated, public broadcaster VTM said without giving further details.
Minister president of the Brussels-Capital region,Rudi Vervoort, calls on national unity: "Democracy, our values, are strongest, and will conquer."
The entire transport system in Brussels has come to a standstill. The effect on the rest of Europe has been immediate: The closure of Brussels airport has led to the cancelling or rerouting of some 1.000 flights according to AFP. The effect was felt in the rest of Europe as authorities strengthened security and checks everywhere.
Neighbouring countries like France, Germany and the Netherlands have reinforced border controls. European capitals like London, Paris, Francfort, Copenhagen and Prague have introduced tighter security in airports, train and underground stations. France's interior minister has announced the deployment of an extra 1.600 police and gendarmes.
Hearses are arriving at Brussels airport says a Wall Street Journal's reporter in Brussels.
Brussels railway stations will reopen at 4pm with increased military presence - Belgium newspapers
"And now, the silence" by Antoine Bayet, director of digital news of France Info.
Two key railway stations in Brussels will reopen at 1500 GMT to allow for traffic to and from Belgium's capital, but the central station will remain closed for now - Brussels police
US President Barack Obama to speak on Brussels attack from Cuba where he is on historic visit.
Obama says the thoughts and prayers of the American people are with the people of Belgium following the attacks.
The government in Belgium has announced three days of national mourning following the attacks against the airport and underground in Brussels that killed at least 34 people (source AFP).
Islamic State has claimed responsibility for the two bomb attacks in Brussels on Tuesday, a news agency affiliated with the group said - source Reuters.