Armed extremists of the banned outfit descended on the station on Chapra-Gopalganj section of Northwest Railway, planted an explosive devise on the track near the outer signal and detonated it damaging about two metre stretch of the line, Railway Protection Force sources said.

However, there were no casualties in the blast. Traffic on the metre gauge line, on which no express trains ply, has been suspended and repair work is on, sources said.

The north Bihar west-zone committee of CPI(Maoist) has called a 24-hour shutdown on Sunday in the districts of Saran, Tirhut and Champaran to protest the recent arrest of its secretary Lal Babu Sahni alias Bhaskarji and the alleged ill-treatment given to him in high security Beur Central Jail in Patna.