CHENNAI: After a cluster of cases reported at IIT Madras on Thursday, the number of cases of COVID-19 further went up to 39. One imported case of a passenger from Singapore testing positive was reported at the International airport. Another patient who had travelled from Maharashtra also tested positive at the domestic airport. Chennai itself recorded 21 cases on Thursday, while six cases were reported in Chengalpattu. About 18,816 samples were tested in the State, and the TPR stood at 0.2 per cent. Chennai saw a TPR of 0.8 pc, while Chengalpattu and Ranipet had 0.7 pc TPR. No deaths were reported due to infection, maintaining the toll so far to 38,025.