Opposition party leaders, while expressing condolences over the deaths of more than 200 passengers in the Odisha train accident, have raised questions about the signalling system of the railways which purportedly led to the crash. More than 233 people were killed and over 900 injured in the crash involving the Bengaluru-Howrah Superfast Express, the Shalimar-Chennai Central Coromandel Express and a goods train on Friday.