An Electrical Multiple Unit at the Arakkonam yard rolled for 300 metres on its own before derailing early on Sunday morning, affecting the movement of three express trains and a couple of EMUs towards Chennai by more than an hour.
Railway officials said the suburban train was stationed at the yard for routine service. “There was no loco pilot in the train. Around 4 a.m., the train rolled for 300 metres on the newly laid track between Arakkonam and Tiruvallur stations before it derailed,” an official said.
The derailment disrupted signals on the line towards Chennai. Train services were affected from 4 a.m. to 5.15 a.m. Three express trains including Mangalore-Chennai Mail and Sathya Sai Prashanthi Nilayam Express and two suburban trains were stopped at various locations, he said.
A departmental probe would be launched into the incident, officials said.
