An Italian grandmother bought a sack of potatoes only to discover a live grenade in the bag.Olga Mauriello, 74, from Giorgio a Cremano, near Naples, was left shocked after finding the grenade had no pin and was still active.Olga revealed: "I went to the market to buy some potatoes and that's where the bomb was. But this bomb was covered in dirt, and I put it in water and got all dirt off. And then I realised 'It's a bomb!' " Police confirmed the grenade was the same type used by US soldiers in Europe during World War II.Explosive experts safely detonated the grenade.