NIA officials, probing the Burdwan blast, Tuesday found bottles containing explosives used to make improvised explosive devices for the blast from a pond near the site in Burdwan district.
The National Investigation Agency officers quizzed one of the suspects - who was arrested Nov 10 - in connection with the Oct 2 blast for information on the explosives.
The suspect said he had stashed the bottles in a small shop in the semi-urban colony of Khargagarh.
When the NIA officers went to the shop and spoke to the shop-owner, he said he had thrown the bottles in a nearby pond.
The shop-owner was detained for questioning.
It has been alleged that a Jamaat-ul-Mujahideen Bangladesh ultra named Sheikh, employed with a medicine company, had obtained the acids used for making the explosives.
