Four passengers, who returned from the UK on Sunday, tested Covid positive at the city airport, Karnataka Health Minister K. Sudhakar said.

"Of the 289 passengers who took the RT-PCR test on arrival from London, 4 turned positive. They have been quarantined," he said in a statement.

Of the total, 273 were passengers (146 men, 95 women and 32 children) while 16 were crew members.

"Swab samples of the infected passengers have been sent to the National Institute of Mental Health and Neuro-Sciences (Nimhans) here to ascertain the strain of the virus," said Sudhakar.

The returnees were the first batch of passengers who flew into the city from London after flights from the UK resumed on January 8. Flights were suspended since December 23 due to the detection of a new Covid virus strain there.

Of the 3,965 passengers who returned to the state from the UK between December 9-22, 40 tested positive, with 11 of them having the new UK virus strain. Some of their primary contacts also tested positive and have been quarantined.

The Minister, who is a doctor himself, visited the Kempegowda international airport on Saturday to inspect the screening arrangements for Covid test of passengers returning from London and San Francisco on early Monday.

As per the revised guidelines of the Union Home Ministry and the standard operating procedures of the Union Health Ministry, all UK returnees to the state have to undergo the RT-PCR test at the airport on landing even if they flew in with a negative test report, which has been mandatory.

"If passengers do not carry a negative report, they will be tested on arrival at the airport through the RT-PCR method and quarantined for 14 days if they are Covid positive," the state Health Department has said.