The Army's top secret operational plans and deployment along the Indo-China border could have been compromised because a top secret letter written by one of the Corps went missing, sources have said.The letter was written by Tezpur-based 4 Corps to Rangia-based 21 Mountain Division a couple of years ago, sources said. It went missing within a week of its receipt and it is still untraceable, they added.Around six military personnel have been indicted by a Court of Inquiry (CoI) and could face disciplinary action for the leakage, sources said. The incident happened when General V K Singh was the Army Chief.The sources also said at that point of time, the 21 Mountain Division was being commanded by Major General N S Ghei, who was later promoted to the rank of a Lieutenant General and is presently commanding the Bathinda-based 10 Corps along Pakistan border.It is not yet clear whether Defence Ministry was informed by the top Army brass about the loss of such a sensitive letter.

The Army is in the process of developing its capabilities along the boundary with China which includes raising of additional 90,000 troops under a yet-to-be-raised Mountain Strike Corps.