The Belgian security and intelligence services on Wednesday continued their manhunt for terrorists who helped organize and carry out the attacks the previous day on Zaventem international airport and Maelbeek metro station, near EU headquarters in Brussels. Following the questioning of a cab driver who claimed that he drove the terrorists to the airport, and initial investigation of the crime scene, counterterror forces raided an apartment in the Schaerbeek neighborhood of northeast Brussels and confiscated explosives and an ISIS flag. The airport will remain closed until at least Thursday. The British government, meanwhile, issued a rare travel advisory for Belgium, warning its citizens to avoid crowded areas across the country. Thirty-five people were killed and more than 250 were wounded in Tuesday's attacks.