SYDNEY (AP) — A judge denied bail Thursday to a 15-year-old boy alleged to be in a network planning terrorist acts and who claimed to be a friend of another teen accused of stabbing a Sydney bishop last month.

The attack on the bishop triggered an investigation that led to the arrests of six teens, ages 14 to 17, who were charged last week with a range of offenses including conspiring to engage in or planning a terrorist act. All remain in custody.

The 15-year-old boy’s lawyer Ahmed Dib had applied for bail Wednesday in the Parramatta Children’s Court, arguing there were exceptional circumstances that required his client’s release.

But Magistrate James Viney ruled such circumstances did not exist. “There is an unacceptable risk to the protection of the community,” Viney said.

Viney said he found the boy’s alleged threats to stab Jewish or Assyrian people, a predominantly Christian ethnic group native to the Middle East, and an alleged assault to be “gravely concerning.”