"Seven trains have been cancelled and the routes of five trains have been diverted in view of the Maoist strike," said a railway official.
The cancelled trains include Palamau Express, Barwadih-Dehri Asansol Express, Tata-Kharagpur Express and Chakradharpur-Gomo Express.
The trains, whose routes had been diverted include Howrah-Jabalpur Shaktipunj Express, Howrah Varanasi Intercity Express and Tata-Jammu Tawi Express.
The bandh called by Maoists is a step to protest the killing of their top leader, Cherukuri Rajkumar alias Azad, in Andhra Pradesh on Jul 2 in an alleged shootout.
The rebels claimed that police killed Azad in a staged gunfight after arresting him in Nagpur in Maharashtra.