Tamil Nadu has declared an intense lockdown in five cities from Sunday to break the chain of transmission of the highly contagious novel coronavirus, which has infected more than 1,600 people in the state so far and killed at least 20, Chief Minister Edappadi K. Palaniswami said this afternoon. A four-day intense shutdown has been declared in Chennai, Madurai and Coimbatore from Sunday 6 am, which will continue till 9 pm on Wednesday. In Tirupur and Salem, restrictions will be intensified for three days, starting 6 am on Sunday till 9 pm on Tuesday, Mr Palaniswami said.Most COVID-19 cases in Tamil Nadu – one of the states worst hit by the coronavirus outbreak in the country – have been reported from these five cities. While Chennai alone has 400 cases, Coimbatore has 134 and Tirupur has 110.