Sources said the move was made after a review by senior officials and consultation with the State police chief.

As part of the Z+ category, around 50 commandos and special wing police personnel were deployed on a rotational basis, around the clock, for intensive surveillance and protection. Police personnel with firearms were also deployed, along with a bulletproof vehicle and jammer facility.

As part of a periodic review in consultation with central and State intelligence, a report was produced. After examining the report, the government has downgraded Stalin's Z Plus security to Z category. Under this category, up to 22 personnel will be on duty.

Security arrangements at Stalin's residence on Cenotaph Road have been altered as per the decision.