Maoists blew uprailway tracks in Giridih district of Jharkhand, paralysing train movement for over five hours, a railway official said Tuesday.The incident took place at 10.45 pm on Monday between Chaudhary Bandh station and Chengaro halt under Dhanbad Rail Division of the East Central Railway (ECR), Hajipur zone.Two night patrol staff members were hardly 20 metres away from the spot when the bomb exploded on the track. They immediately alerted the Assistant Station Master (ASM) of Chaudhary Bandh, the DRM said.About one metre-long track was damaged in the explosion, he said.Eight express trains were stopped at various stations on Monday night and 13 trains diverted due to the blast, Dhanbad Rail Division Manager (DRM) Anil Kumar Mishra said.The DRM said both up and down tracks opened for trains at 3.15 am and 3.30 am respectively.