Belgium pressed a huge manhunt on Tuesday after Islamic State bombers attacked Brussels airport and a metro train, killing around 35 people and wounding hundreds as jihadists once again struck at the heart of Europe. Two massive suicide blasts by men with bombs in their bags hit Zaventem Airport, leaving blood and mangled bodies strewn across the check-in hall and sending terrified travellers fleeing. Belgian authorities released pictures of two of the suspects pushing trolleys with their bombs through the terminal and said they were "actively searching" for a third man whose explosives did not to go off.

The Islamic State claimed the bombings, saying "soldiers of the caliphate" had carried out the attacks against "the crusader state" of Belgium.

Leaders across Europe reacted with outrage, with the EU vowing to combat terrorism "with all means necessary" on a continent that has been on high alert for months. "The whole of Europe has been hit," said French President Francois Hollande, whose country is still reeling from November's attacks.

Landmarks from the Eiffel Tower in Paris to Berlin's Brandenburg Gate were lit up in the black, yellow and red of Belgium's national flag in solidarity.

US President Barack Obama vowed to stand with Belgium in the face of the "outrageous" attacks and ordered US flags flown at half mast, while the FBI and New York police said they would send investigators to help.