Bengaluru, April 9 -- The first week of April has been brutal for Tamil Nadu in its fight against the coronavirus disease. The number of Covid-19 cases in the state has multiplied by more than 10 times, from 67 at the end of March to 690 as of Tuesday, April 7. Of these, 637 are linked to those returning from the Tablighi Jamaat conference held in mid-March at the Islamic missionary group's Markaz headquarters in Delhi's Nizamuddin, which has emerged as the biggest Covid-19 hot spot in India....