Three NSW inmates have been charged for allegedly conspiring with a teenage boy and another man over an alleged terror plot targeting government buildings.
The men, aged 21, 22 and 22 were arrested in counter-terrorism raids as part of Operation Appleby in December 2014 and 2015.
They were each charged with one count of conspiracy to conduct an act in preparation for a terrorist act on Thursday, NSW Police say.
The charges come after a 15-year-old boy and 20-year-old man were arrested and charged in Sydney's west on Thursday for allegedly planning to carry out a terrorist attack on government buildings, including the Sydney Australian Federal Police headquarters.
One of the 22-year-old inmates was scheduled to appear before Sydney Central Local Court on Thursday afternoon.
The other 22-year-old man and the 21-year-old man have been refused police bail and are scheduled to appear before Sydney Central Local Court on December 16.
