Chennai, May 4 -- The Election Commission of India (ECI) on Sunday said a three-tier security system will be in place at counting centres, with around 100,000 security personnel deployed for election security duties, as votes for the Tamil Nadu assembly elections will be counted on Monday. In Chennai alone, police said nearly 20,000 security staff have been deployed. State chief electoral officer (CEO) Archana Patnaik said the first-tier security perimeter extending 100 metres around each counting centre has been established. "...Adequate police personnel will be deployed at entry points," she added. The second-tier, comprising the entry gates of the counting premises will be secured by the state armed police personnel, who would regulate a...