Canberrans have been turned away from Exhibition Park's testing centre, after some of them waited up to eight hours for a Covid test following the return of the virus to the ACT.
The turnaways came after ACT Health stopped accepting new arrivals at the Weston Creek and EPIC testing centres earlier in the evening, and assured those already in line that they would be tested.
However the surge in demand was ultimately too much for testing staff who had worked long hours throughout the day, and people still in line as the last tests were being administered about 10.45pm were told they would need to return home.
A Canberra Health Services spokeswoman said Canberrans had done the right thing by turning out in record numbers to get tested, and asked those who had been turned away from testing sites to please return on Friday.
"We're very sorry, but we have to look after our staff. They'll be back bright and early in the morning," the spokeswoman said.
"It was a record day for the ACT. We've tested more people today than we ever have before in a single day."
Testing at the Brindabella site was also extended from the planned 8pm cut-off to 10pm before staff were able to go home.
The surge in demand for testing came after Canberra reported four cases of community transmission on Thursday, releasing a long list of exposure sites around the territory.
Health authorities urged those who had visited the sites or been in close contact with someone who had to go and get tested.
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But testing sites in Mitchell, Pialligo and Weston Creek were overwhelmed by the demand following the announcement.
The Flemington Road turn-off on Northbourne Avenue was closed and vehicles were diverted to Stirling Avenue.
One woman reported it had taken almost an hour to travel between the Mouat St intersection in Lyneham to the Barton Highway turn-off, a trip that would usually take a few minutes.
The ACT government announced it would ramp up testing capacity at the Mitchell site on Thursday to deal with the surge.
ACT Health Minister Rachel Stephen-Smith reminded Canberrans it was important only those who had been directed to, or had symptoms, went to the clinics for testing.
"Please do not turn up to get tested because you're anxious," she said.
"We really, really need to prioritise the testing for people who need it but if you do have symptoms, absolutely go and get tested at the earliest opportunity."
A new drive-through testing site in Brindabella Business Park opened at 4pm on Thursday, and will be reopening again at 8am on Friday.
Authorities released a list of a number of exposure sites across the nation's capital, including locations in Fyshwick, Braddon, Manuka, Mitchell, Cook, Kingston, Civic and Woden.
Authorities released a number of exposure sites across the nation's capital, including locations in Fyshwick, Braddon, Manuka, Mitchell, Cook, Kingston, Civic and Woden.
Further exposure sites were listed late on Thursday evening, including discount department stores and a Deakin cafe.
Wastewater testing has also identified traces of coronavirus at the City-Central, North Canberra and Woden Valley collection sites, as well as the Lower Molonglo site.
Anyone who attended the Canberra Outlet Centre outside of the individual outlets listed above between 2pm and 3.30pm on August 8 must monitor for symptoms and get tested immediately if they develop, ACT Health has advised.
"ACT Health will be updating the ACT COVID-19 website regularly, with exposure locations posted each day," a spokesperson said.
The ACT entered a snap seven-day lockdown at 5pm on Thursday after coronavirus was detected in the territory.
A Gungahlin man in his 20s was identified as the territory's first positive case in more than a year. He was infectious in the community since Sunday.
A further three cases were announced by Thursday evening - all were close contacts of the first case.
The ACT government has started contact tracing, but the source of the virus is currently unknown.
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