London: British Prime Minister David Cameron will chair an emergency meeting to determine Britain's response to the Brussels terror attacks. The prime minister said Britain's security had been stepped up in the wake of "a very real terror threat" across Europe, BBC reported on Wednesday. Two Britons were injured in the blasts at the city's airport and metro on Tuesday which left 34 people dead. There are also concerns for David Dixon, an IT programmer from Nottingham, whose family said he had not been seen since the attacks. Dixon has lived in Brussels for 10 years, his friends said. Two blasts hit Zaventem airport in Brussels and another explosion took place at a Metro station in the city on Tuesday. At least 34 people were killed and over 200 injured in the blasts. Brussels police have issued a wanted notice for a man seen pushing a luggage trolley through the airport along with two other suspects shortly before the twin explosions. The two other men died in the attacks after detonating suicide devices, a Belgian prosecutor said. The Islamic State (IS) has claimed responsibility for the attacks.