Tragedy struck the renowned Ruia Hospital in Andhra Pradesh's Tirupati on Monday as 11 Covid patients lost their lives due to an interruption in oxygen supply, Chittoor District Collector Harinarayan said.The district authorities attributed the deaths to a five-minute delay in the arrival of an oxygen tanker at the hospital. However, with the oxygen supply restored immediately, a major tragedy was averted, the Collector said.Around a thousand patients are undergoing treatment at the hospital. As the oxygen supply got affected all of a sudden, many patients began to choke. Doctors were seen attempting CPR procedures to revive the oxygen-starved patients, while kin of the patients used cardboard pieces to fan and revive them.An inquiry has been initiated into the incident. Andhra Pradesh Chief Minister Y.S. Jaganmohan Reddy, who was apprised of the tragedy, has asked for a report.