The New York Police Department is tightening security across its mass-transit points Tuesday, on news of the Brussels terror attacks that left at least 21 people dead. A spokesman said New Yorkers should expect to see an increased police presence at subway stations, landmarks, bridges, and tunnels, following the attacks at Brussels Airport and in the Belgian capital’s Maalbeek subway station. A Belgian public prosecutor said at least one of the explosions was caused by a suicide attack.
