"A 15-year-old boy charged by counter-terrorism police is a student at Bass High School, in Bass Hill in Sydney’s west, the ABC understands.
Police have alleged the teenager and a 20-year-old man are associates of those responsible for the murder of New South Wales Police employee Curtis Cheng.
Another three people are expected to be charged this afternoon.
It is believed the Department of Education contacted law enforcement agencies to discuss a concern that the boy was radicalising other students within the school.
A spokesperson for New South Wales Education Minister Adrian Piccoli said his office was made aware of the student’s arrest. The Education Department is working closely with the school.
The pair have been charged with conspiracy to conduct an act in preparation for a terrorist act, and police expect to charge another three people with the same offence this afternoon.
The 20-year-old is Ibrahim Ghazzawy from Raby. The teenager cannot be named for legal reasons but is from Georges Hall.
The arrests were carried out by officers from the Australian Federal Police (AFP) and the New South Wales Police, as part of Operation Appleby."