Close to 40 cases are now linked to the Casula hotel outbreak of COVID-19, and NSW Health is racing to track down the source of three cases which have not been linked to any previous identified venues.
At her daily update, NSW Chief Health Officer Dr Kerry Chant said there had been 10 new cases identified in the 24 hours to 8pm on Wednesday, and two new cases identified overnight.
Four were associated with hotel quarantine, three - a man in 30s , a child, and a man in his 80s - were linked to the Crossroads Hotel, Dr Chant said.
The three which are still under investigation are linked to the South Western Sydney cluster, she said, but has not been linked to any of the listed venues so far.
The health department is re-interviewing them and their contacts to see if any links can be found.
"We are concerned when we find cases that can't be linked back, because that indicates we've missed a chain," Dr Chant said.
"We do need people to continue to practise social distancing, isolate with the minimum of symptoms and get tested."
Since 8pm, there have been an extra two cases identified: a teen who attended a Brighton Le Sands club and a person who flew from Victoria to Ballina on July 12.
Dr Chant said that person was wearing a surgical mask and self isolating, but NSW Health is doing contact tracing in regard to flight JQ466.
She said 22,836 tests had been performed across the state with 3466 done in South Western Sydney.
She also warned that the wider community needed to continue to take extreme caution in the coming weeks, and said not to assume close friends or family were not going to transmit the virus.
"We have the impression that the people we're associating with day to day in, day out, are safe and we might let down our guard," she said.
"Don't have the perception that you're safe in that environment."
"This is not the time to be throwing those big parties or going out,
"Don't go out with your group of friends if you've got even the mildest of symptoms.
For community sport this weekend, just want to again urge everyone to minimise the spectators. Don't go there is you've been in any of these sites [here COVID-19 has been transmitted].
"This is a critical time in our response phase as we try to mop up any community transmission."
Meantime, in Victoria, there have been more than 300 new cases of coronavirus identified in one day of the first time. Premier Daniel Andrews said there had been 317 cases recorded in the past 24 hours, and two men in their 80s have died.