Forty passengers flying in from different countries tested positive for the novel coronavirus upon landing at Peshawar's Bacha Khan International Airport on Thursday, Peshawar Additional Deputy Commissioner Ashfaq Khan said.

The infected passengers were shifted to the district quarantine centre. Around 100 passengers who arrived from different countries are currently staying at the quarantine centre, the official said, adding that the government was providing all the facilities to them.

Earlier, reports emerged of scuffles between the passengers and airport staff, with the passengers claiming the test results were "falsified".

The development comes amid concerns that passengers with the coronavirus are entering the country using fake PCR tests.

Earlier this week, the Civil Aviation Authority (CAA) revoked the permission granted to a private airline for flying from Dubai to Peshawar after it carried 27 passengers on Sunday who tested positive for Covid-19.

It was the second time this month that the government's coronavirus SOPs had been violated by the private airline after it transported 24 coronavirus-positive passengers on May 10 from Dubai to Peshawar.

Last week, the CAA had noted with "grave concern" that passengers travelling to Pakistan — especially from Gulf states — tested positive for the virus upon arrival despite being in possession of negative PCR test results.

"Upon conducting an investigation into the issue, it has been found that passengers travelled to Pakistan using fake PCR negative test results and endangered not only passengers travelling with them, but also undermined the intense efforts being made at the national level to curb the spread of Covid-19," the CAA had said in a notification.

The authority had directed all airlines operating to and from Pakistan to ensure that all passengers travelling to the country possessed test results from government-approved labs and that no test results were accepted without a valid QR code.

On May 1, the CAA had issued fresh operational protocols for inbound passenger flights, directing all international airlines to ensure that standard operating procedures were followed in letter and spirit by all passengers and crew.

The CAA had said that all passengers would also be required to undergo RAT (Rapid Antigen Test) upon arrival at the respective airports in Pakistan and non-compliance would result in strict punitive action.

The measures were taken to ensure the safety of passengers and crew and to minimise the risks associated with Covid-19, it said.