These children were trying to break the shell to sell it to a scrap dealer,' Singh said.

Two boys died on the spot while the third succumbed to injuries at the Postgraduate Institute of Medical Education and Research (PGIMER) in Chandigarh.

Indian Army's Western Command headquarters is situated at Chandi Mandir, 2 km from here.

Meanwhile, Shyam Lal, an eyewitness to the incident, said: 'I saw these boys playing with an unusual metal object. After few minutes, I heard a deafening noise. We rushed to the spot and found these boys bleeding profusely.'