Chaos erupted in the heart of the nation's capital last night as the White House Correspondents' Dinner - Washington's most glitzy annual tradition - was shattered by gunfire. What began as a night of high-society networking and political ribbing at the Washington Hilton turned into a harrowing survival scene. A-list celebrities, government officials and media power players were calmly seated in the ballroom when the festive atmosphere was punctured by the sound of a violent security breach.