UPDATE 6:45 P.M. Click here for the maps and pictures that tell the story.
UPDATE 4:30 P.M., including photo of suspects
More than 30 people are dead and more than 200 wounded after explosions struck Brussels during the Tuesday morning rush hour, Belgian officials say. Two blasts hit the international airport; another struck a metro station. Belgium has issued a Level 4 alert, denoting "serious and imminent attack."