Police have halted their search of the area around Gibraltar Falls where cries for help were heard on Monday.
ACT Policing's search and rescue team has not yet found anyone after an extensive search which ended at 4pm on Tuesday.
So far, no one has been reported missing in the area near the waterfall.
As a result, authorities did not resume the search on Wednesday morning. Final advice from the officer on the case will decide whether to call off the search for a possible missing person.
The search began after witnesses heard calls for help on Monday evening. Police believed this could have meant that someone had gone missing.
But after 24 hours of search, the effort was called off as night fell. A spokesman said at the time the situation would be reassessed the following morning.
"ACT Policing has suspended the search at Gibraltar Falls, with nothing of interest located following an extensive search of the area today. Investigations into the circumstances of this matter are ongoing," the police said.
On Monday at about 5.30pm, people parked off Corin Road near the closed Gibraltar Falls entrance said they heard calls for help.
Police and ACT Parks rangers searched the area but no one in need was found. Drones were also used in the search.
The search was suspended about midnight on Monday and resumed early Tuesday morning.
Police urgently want to speak to anyone who visited the waterfall or were in the vicinity on Monday afternoon.
Community members who knew family or friends visiting the area on Monday have also been asked to contact ACT Policing.
Anyone with information that could assist police is urged to contact ACT Policing Communications on 131 444 quoting reference 7516648.