Tripura has become the fifth state in the northeast to become Covid-19 free. The state had two cases - both have been cured and discharged. Tripura topped the list for tests with 1,051 tests per million people. A total of 4,450 people out of the state's 4 million people have been tested so far. There have been no new reported cases in the state in the last 14 days. Sikkim, Nagaland, Arunachal Pradesh and Manipur are the four other states that are Covid-19 free.