Timer watch, procured in bulk from a shop in Guwahati, was again used in the seven blasts yesterday when Modi was addressing a political rally in Gandhi Maidan at Patna in which six people were killed and over 80 injured, official sources said.
They said the arrested persons -- Tausim and Imtiyaz -- were being questioned for their role in the Bodh Gaya blasts on July 7. No one was killed in those blasts.
Bihar Director General of Police Abhyanand was not available for comments.
About the probe, the sources said the duo was being questioned by a team of National Investigation Agency about their role in Bodh Gaya and their linkages with Indian Mujahideen terror group.
Searches were being conducted in Bihar and neighbouring Jharkhand where police and security agencies have claimed to have found ammonium nitrate, materials used to make IEDs, pressure cooker and extremist literature. Four people have been detained in connection with this.