Batting legend Sachin Tendulkar's security cover has been downgraded, while that of Shiv-Sena MLA Aaditya Thackeray upgraded to 'Z' category, an official said. The changes in security-cover were made after a review was undertaken by a Maharashtra-government committee on threat perception to them, he said. Besides Tendulkar and Aaditya, security-cover of more than 90-prominent-citizens were reviewed by the committee at a-recent-meeting, the official said.