Patna authorities on Thursday claimed to have busted a racket that provided fake RT-PCR test reports to airline passengers showing they were Covid-negative for Rs 2,000 each.

Four suspects were detained during a raid on Wednesday night on a so-called lab, Plasma Diagnostics, which operated 800 metres from Patna airport. It was sealed on Thursday.

Passengers travelling from Patna to cities in several states — including Maharashtra, Bengal, Karnataka, Kerala, Punjab and Rajasthan — need to carry a negative RT-PCR report. Depending on the destination, the reports cannot be older than 48, 72 or 96 hours.

Airport sources said the racketeers stationed touts at the terminal who kept an eye out for passengers who came without realising they would need a negative RT-PCR test report, and arranged fake reports in a few minutes.

Airlines — which have a QR code-based system of checking the authenticity of RT-PCR reports that is, however, not foolproof — caught several passengers trying to board flights with fake reports and informed airport director Bhupesh Negi.

“The airlines stopped these passengers from boarding and reported the cases to me. I informed the district magistrate,” Negi told The Telegraph.

Investigations revealed that several of the eventually offloaded passengers had earlier visited Plasma Diagnostics with the touts. District magistrate Chandrashekhar Singh asked civil surgeon Vibha Kumari to form a team of health officials to raid Plasma.

“We sent a team led by our additional chief medical officer. Other officials from the district administration and the police assisted it,” Vibha said on Thursday.

Vibha said: “Plasma Diagnostics turned out to be a shop selling spectacles. It had no laboratory or machines to conduct Covid tests. Neither had we given it permission to conduct RT-PCR tests or collect samples for such tests. We sealed it today.”

City superintendent of police (central) Ambarish Rahul said an FIR would be registered.

Negi could not put an approximate figure on the number of passengers detected carrying fake RT-PCR reports.

Sources suggested many others with fake reports would have beaten the system. Some states such as Kerala have reported catching air passengers who arrived with fake RT-PCR certificates.

Negi could not explain why those detected with fake certificates were allowed to go without any legal action against them. “Taking such action is the responsibility of the airlines,” he said.