Gopinath, a marketing executive from Vellore district in Tamil Nadu, had been tending to his 82-year-old ailing mother Lalitha from April 6. She had been admitted to the Vellore Adukkamparai government hospital with a lung infection, and to his relief, she tested negative for coronavirus. But on Monday, hours after he was promised that she could be shifted to a regular ward despite being on a ventilator, Lalitha suddenly died. At close to 2 pm, says Gopinath, her oxygen levels began to dip dangerously as supply of the essential gas was completely cut off to the ward. And Lalitha was amongst at least five patients on ventilator to die allegedly due to the shortage of oxygen in the government hospital within the next hour. "The oxygen supply stopped around 12 noon and they were using cylinders to keep patients going. By 2 pm, they were completely out of oxygen. My mother's oxygen levels then dipped from 92 to 30," alleges Gopinath. "When we began to inquire, the hospital staff said they were looking into it. Her oxygen levels then further dipped to 9 and her pulse stopped. Then they just claimed she died because of the infection," he adds, shocked. Along with Lalitha, her son alleges, two more women and men who were dependent on oxygen also died in the same ward. According to reports, the other deceased persons are Rajeswari (68), Prem (40), Selvaraj (66) and a 28-year-old woman who has not been named. "It was the hospital's lax nature that resulted in their deaths and now they are not even taking responsibility," he alleges. The relative of another patient, Rajeshwari, who died in the ward, too, told to the media outside that there was an unexpected dip in oxygen levels, “Suddenly oxygen levels began decreasing. If they had filled it earlier… Tanks emptied at once for three patients… he was holding without oxygen for half an hour. Doctor kept saying there’s no one for oxygen," the woman told Puthiyathalaimurai TV. Watch: The woman speaks to media Government officials and the hospital are, however, denying that the shortage caused the deaths. Speaking to TNM, Deputy Director of Health, Vellore district Manivannan says, "There was no oxygen shortage. These people saw some service work being done and assumed it was a shortage. But they all died due to the problems that they came to the hospital with." Relatives, however, allege that the state is covering the real cause of the deaths. "All of them died within minutes of each other. How is that possible?" asks Gopinath. "The way they have treated patients is pathetic and now they are washing their hands off this."