Section 46C(1)(a) in The Orissa Panchayat Samiti Election Rules, 1991
(a)any ballot box used at a polling station or at a place fixed for the poll is unlawfully taken out of the custody of the Presiding Officer or the Polling Officer accidentally or intentionally destroyed or lost, or is damaged or tampered with, to such an extent that the result of the poll at that polling station or place cannot be ascertained; or