Bishop Mar Mari Emmanuel was stabbed during a church service. Photo: Screenshot / YouTube
Authorities have designated a knife attack at a Sydney church as a terrorist act.
At least four people, including Bishop Mar Mari Emmanuel, were injured during a service at Christ the Good Shepherd Church in the suburb of Wakeley.
Police arrested a 15-year-old boy at the scene and said they were forced to hold him at the church for his own safety after a crowd gathered outside, demanding the attacker be brought out.
It was the second major stabbing in just three days after six people were killed at Westfield Bondi Junction on Saturday.
Speaking to the ABC, NSW Premier Chris Minns said the church stabbing was a "terrorist act".
"That decision was validated by the Minister for police at 1:44am with her contacting me at 2am this morning," he said.
NSW Police Commissioner Karen Webb also referred to the incident a "terrorist act".
"Strikeforce Katrina has been established to investigate that side of the events last night and a referral has been made and agreed to by the joint counterterrorism investigation team."
She had spoken about the incident with the counterterrorism team for over an hour on Tuesday morning, she told the ABC.
"The things that influenced my decision to declare this a terrorist incident was the actions of the individual who attended, we will allege attended that church ... armed with a knife and stabbed the bishop and priest.
"We believe there are elements that are satisfied in terms of religious-motivated extremism."
Webb said the church service's livestream informed her declaration of the event as a terrorist attack.
The teenager made comments to the bishop "centred around religion" as he approached, she said.
The 15-year-old was known to police, but not "well-known", she told the ABC.
"I think the important thing is here is ... he wasn't known to us from a terrorism point of view, he was not on any terror watchlist.
"This is the first time this individual has come to our attention in this manner."
A livestream of the event, hosted on the church's social media page, showed the bishop being stabbed several times in the head and chest.
A separate eyewitness video, which has been verified by Reuters, showed the suspect being pinned to the ground.
A voice, speaking in Arabic, said: "If they didn't insult my prophet, I wouldn't have come here. If he didn't involve himself in my religion, I would not have come here."