One of Canberra's new locally-acquired COVID-19 cases has "no obvious links", while the second attended a busy nightclub.
The ACT will also receive about 14,000 extra doses of the Pfizer vaccine, following the announcement that the federal government acquired an extra million doses that will begin arriving in Australia on Monday.
There are up to 5,700 potential close contacts who have come forward to ACT Health while the list of exposure sites grows to more than 40.
There are now nine active coronavirus cases in the territory.
In the past 24 hours, 3292 negative test results have been returned after another record day of testing with almost 6000 swabs taken.
The ACT has reported two new cases of COVID-19 to 7pm Saturday. Both cases are men in their 20s.
One new case has "no obvious links" to other identified cases in the ACT.
Chief Minister Andrew Barr said investigations were underway to determine how he got the infection.
The second case is linked to the Fiction nightclub, which was among the first exposure sites revealed on Thursday.
The city nightclub is a close contact exposure site on August 7 from 9pm to midnight and through until 4.45am Sunday morning.
This man attended the club from 1am to 4am.
ACT Chief Health Officer Dr Kerryn Coleman said it was essential anyone at the nightclub during that period get tested and remain isolated.
"If you are a close or casual contact, please take this seriously and follow advice," Dr Coleman said.
The source of infection in a 14-year-old Gold Creek School student also remains a mystery. A close contact of that student has also tested positive.
"There are investigations ongoing for one or two others about whether they're possible links," Dr Coleman said.
A pop-up testing clinic has been set up in Gungahlin for people affected by the Gold Creek School exposure sites.
Dr Coleman said the year groups most likely exposed were being prioritised and expected it would take until Tuesday to get through the thousands of people affected.
The Chief Minister said Canberrans had responded well to the challenge Covid had thrown, and urged residents to "keep doing what you're doing".
"It's been so pleasing to see the seriousness in which Canberrans are responding to the challenge that we have. I understand people are concerned and anxious, it's a challenging time for everyone," he said.
"The response from the Canberra community has been fantastic."
High demand has once again hit the Weston Creek walk-in centre and authorities are urging those who can to attend sites at EPIC or Brindabella Business Park.
Health Minister Rachel Stephen-Smith said the Department of Defence had provided 16 clinical staff to join testing efforts from Monday.
Record numbers have turned out to be tested for COVID-19 since a seven-day lockdown was announced on Thursday, with authorities urging close contacts to be prioritised.
Wait times took a dramatic turn on Saturday afternoon with close to no wait at the EPIC drive-through by evening, after days of Canberrans waiting in their cars for up to 12 hours.
The first case, which sparked the territory lockdown, has been linked to Sydney and confirmed as the highly transmissible Delta strain, but health officials say they are not yet certain how the virus returned to the territory.
