The police in Tamil Nadu have launched a massive search for a man who went missing after he was released from the government hospital in Villupuram due to a “clerical error” but was later found to be infected with the coronavirus, The Hindu reported.

The 30-year-old man from Delhi was admitted to the Villupuram Government Hospital on Monday after he developed a fever. He had come to Tamil Nadu after an interview in Puducherry last month, the newspaper reported quoting unidentified health officials.

The officials told the newspaper that they followed the protocol for handling suspected Covid-19 cases. “Throat swabs of the patient along with test samples of others were sent to the Villupuram Government Medical College and Hospital for testing the same day,” the officials said.

The staff at the Villupuram Government Hospital erroneously marked his test results negative, after which he was discharged, officials said. Three other people who tested positive for Covid-19 at the hospital were also released because of a mistake but they have been located, The Times of India reported.

Villupuram Superintendent of Police P Jayakumar told the newspaper that they have managed to trace three patients. “We are trying to trace the fourth patient, who is from Delhi,” he said.

Follow live updates on coronavirus

Read our top 10 Covid-19 updates

Tamil Nadu Health Secretary Beela Rajesh, however, denied that there had been any such error . “All patients who tested positive in Villupuram were under the government’s watch,” she said, according to the newspaper. “We did not lose track of them. There cannot be a clerical error of patients in isolation wards.”

Tamil Nadu has seen a huge spike in the number of coronavirus cases over the last few days. According to the Ministry of Health and Family Welfare, there are 738 cases of coronavirus in the state and eight people have died.