The men were taken into custody in raids across the major city early on Tuesday.
Two of those arrested were identified as young men aged 20 and 23 and were charged with being members of Daesh. The younger man has also been accused of plotting an unspecified attack in Sydney, which police authorities said was in the early stages of planning.
The third detainee, a 30-year-old man, has been charged with welfare fraud, reports said, citing officials, without elaborating on how he was tied to the alleged terror plots.
“The man indicated a range of potential targets. These include the following: police stations, defense establishments, embassies and consulates, courts and churches,” Australia’s Federal Police Assistant Commissioner Ian McCartney declared during a Tuesday press briefing in Sydney, referring to one of the suspects.
All three are due to appear in court either later on Tuesday or Wednesday.
Australia has been on heightened alert for terrorist attacks since 2014, when a hostage standoff occurred at a café in Sydney. According to officials, 16 terror plots have so far been foiled.
In December 2016, Australian police in the city of Melbourne announced the arrest of five Daesh-linked suspects, accusing them of planning to carry out a series of Christmas Day terrorist attacks across the city.
5 arrested over terror plot in MelbournePolice arrest five people suspected of plotting Christmas Day terrorist attacks in Melbourne.
The Australian prime minister at the time alleged that the thwarted attack was one of the biggest “terrorist” plots prevented by police in years amid reports that the suspects were inspired by the Daesh terror group.
Also in December 2015, police in Sydney announced the arrest of two young men for alleged plots to target locations that included a key naval base in the port city, adding that the operation was part of an effort to foil potential attacks by home-grown terrorists linked to or inspired by Daesh.