Police recovered 20 grenades, four foreign pistols, 40 bullets and a huge number of bomb making materials from a house at Juanpur Kuthibari village of Sherpur upazila in Bogra on Monday morning. It can be here mentioned that at least two youths were killed and one injured in an explosion while they were making bombs in the house on Sunday night.One died on the spot and another died at Ziaur Rahman Medical College Hospital. But the deceased could not be identified immediately. Two youths rented the house several days ago, it is learnt.