CHENNAI: A 20-year old man who travelled by train from Delhi to the city tested positive for coronavirus on Wednesday, becoming Tamil Nadu 's second COVID-19 patient , over ten days after the first case surfaced in the state, Health Minister C Vijaya Baskar said.Incidentally, the first patient, a 45-year old engineer, has been discharged from hospital after his recovery, the Minister announced.On the latest case, he indicated the patient did not have any history of foreign travel, describing him as a domestic case.The youth, hailing from Delhi was currently in the isolation ward at the Rajiv Gandhi Government General Hospital (RGGGH) here and being monitored closely, he said adding efforts would be launched immediately to trace those whom he had come into contact in recent days.He is a 20-year-old hailing from New Delhi While coming to Chennai he was not showing any symptoms. But, yesterday he visited the RGGGH with symptoms of coronavirus and we collected his samples."A few hours ago, I received message from the Dean (of the hospital) that he has tested positive for the virus. Now we will be tracking the epidemiology link, Vijaya Baskar told reporters on Wednesday evening.The Minister, however, declined to entertain questions on when the patient arrived here and about his travel history."All I can say is the first positive case was imported since that patient had visited Oman. This is a domestic case. He has come to Tamil Nadu through train", he said.The Minister said the patient initially did not show any symptoms upon his arrival from New Delhi but later he developed symptoms of coronavirus. "We will trace his contacts immediately."Earlier, in a social media post, he said: "Chennai reports the second positive case for #Covid19. The patient hails from New Delhi, is in isolation and stable under the observation of the expert team treating #Covid19."Replying to a question, Vijaya Baskar said the first COVID-19 patient in the state had already been discharged and was currently under home quarantine.The Minister had recently said the man from neighbouring Kancheepuram, who tested positive on March 7, had twice tested negative for coronavirus and would be discharged soon.So far 1,89,750 people had been screened at airports and 32 had been admitted to isolation wards in various hospitals, he said on Wednesday, adding of the total 222 samples tested in the state, as many as 166 had tested negative and results of the remaining were awaited.Meanwhile, continuing his inspection of preventive measures at various places, the minister accompanied by Health Secretary Beela Rajesh, Director General of Police (Railways) Sylendra Babu and other senior officials reviewed the preventive steps taken at the Chennai Egmore Railway Station.The state government has already announced a lockdown, declaring holidays for all educational institutions and closure of places thronged by public in large numbers such as liquor bars, theatres, malls and resorts till March 31.