SYDNEY - A more contagious variant of COVID-19 first reported in the UK has been detected in three people associated with the Australian Open tennis event, officials confirmed on Saturday evening.

The three people are not players and initially tested positive for the virus shortly after arriving in Australia last week.

All three have been in strict quarantine since their arrival.

"The residents arrived in Melbourne on a dedicated Australian Open charter flight on 15 January and returned their first positive tests on 15, 17 and 18 January," a spokesperson for COVID-19 Quarantine Victoria said.

"The three residents include two men in their 30s and a man in his 50s and all are non-players."

One of the cases linked with the event was reclassified on Sunday taking the total number to nine. There are roughly 70 competitors considered close contacts of those cases.

All those considered close contacts are required to undergo two weeks of strict isolation at a designated quarantine hotel.