CHENNAI, June 20: Chaos reigned at the Chennai Central Railway station when rail traffic was affected as two empty bogies of the Charminar Express derailed. The accident happened as the rake was being pulled into the 9th platform from the yeard for departure this evening. Several trains were delayed and the Charminar Express, scheduled to leave at 6-10 pm today was rescheduled to leave at 6 am on June 21.