People from the Muslim community, who had participated in Tablighi Jamaat in Delhi's Nizamuddin, should come forward and undergo COVID-19 test, said C Kadhiravan Erode District Collector on Wednesday.
Sulthanpet, Manickam Palayam and BP Agraharam, where Muslim population density is high, have been cordoned off, the District Collector added.
Thousands are said to have attended the three-day Tablighi Jamaat conference at the Markaz Nizamuddin mosque, with the Tamil Nadu health authorities estimating that around 1,500 of them were from the state.
Delhi Health Minister Satyendar Jain had said that the officials are not certain of the number of people who participated in the event but it is being estimated that 1,500-1,700 people had assembled at the Markaz building.
The religious gathering was held at the Markaz building in Nizamuddin between March 13-15 violating lockdown conditions.
The total number of coronavirus cases in India climbed to 1397 on Tuesday after 146 new infections were reported in the past 24 hours across the country.
The death toll due to the COVID-19 rose to 35 while 123 cases were cured or discharged after treatment, the Ministry of Health and Family Welfare said.