Brussels was rocked by a terrorist attack on 22 March, killing more than 30 people and injuring over 250.

Twin blasts hit the check-in area of Zaventem airport at 7am GMT. Just over an hour later, another bomb exploded at Maelbeek metro station in the city centre.

Brothers Khalid and Brahim el-Bakraoui have been identified as behind the attacks. Brahim was the suicide bomber involved in the Zaventem airport blast, whilst Khalid was the suicide bomber behind the Maelbeek metro explosion. The third suspect, Najim Laachraoui, is still at large and a manhunt is under way.

Brussels attack LIVE: Third Zaventem attacker still at large as Isis suicide bombers identified

Islamist militant group Isis claimed responsibility for the attacks, which came four days after the capture in Brussels of Salah Abdesla, the main suspect in the terrorist attacks on Paris on 13 November

World leaders spoke out against the atrocity. UK Prime Minister David Cameron said in the wake of the attacks: "These are appalling and savage terrorist attacks and I've just spoken to the prime minister of Belgium to give our sympathies and our condolences to the Belgian people and we absolutely stand with them at this very difficult time."

Belgium has raised its terror threat to its highest level following the attacks, with troops and police deployed across the country.