South Australia has reported its first locally acquired cases of COVID-19 since reopening the state's borders last week.
SA Health says two men in their 50s have tested positive for the virus after attending the same event as interstate travellers.
"While the cases are currently under investigation, we believe the virus was passed on from an interstate traveller at the event," it said in a statement on Wednesday.
"We expect exposure locations to follow."
A child who recently returned from overseas has also tested positive for the virus, taking the number of active infections in SA to nine.
There have been 13 cases since the border rules were relaxed, but all have involved interstate or overseas travellers.
Under current arrangements, SA is open to vaccinated travellers from all states and territories, with some requirements for testing and quarantine.
International arrivals are required to quarantine for 14 days, regardless of where they come from.
Local restrictions, such as mandatory mask-wearing on public transport and in most venues, also remain.
The state's transition committee met on Tuesday but left all travel and local restrictions unchanged despite concerns over the new Omicron variant of the virus.
Premier Steven Marshall said previously there was an "inevitability" about cases in South Australia under the new border rules.
"But what we want to do is to get to those cases as early as possible," he said.
"So that we're minimising the number of people who need to have testing or potentially go into isolation."
