Two coaches of Bangalore-Chennai Mail derailed near Basin Bridge here at 4.25am on Wednesday. Passengers were safe.. The derailed coaches include first AC and second AC coaches. The accident affected train services to Chennai Central railway station. Railway officials arrived at the spot soon after the incident. Passengers from the two derailed coaches were shifted to other compartments. The train reached Chennai Central around 5.30 am. Shunting engines were pressed into service. The derailed coaches were placed back on track by 7.45 am and taken away.