Australian police say a knife attack in Sydney that wounded a bishop and a priest during a church service as horrified worshippers watched online and in person was an act of terrorism.

Police arrested a 16-year-old boy on Tuesday after the stabbing at Christ the Good Shepherd Church that injured bishop Mar Mari Emmanuel and a priest. Both are expected to survive.

New South Wales police commissioner Karen Webb said the suspect’s comments pointed to a religious motive for the attack.

She said: “We’ll allege there’s a degree of premeditation on the basis that this person has travelled to that location, which is not near his residential address, he has travelled with a knife and subsequently the bishop and the priest have been stabbed.

APTOPIX Australia Church Stabbings
A crowd of hundreds seeking revenge gathered outside the Orthodox Assyrian church (Mark Baker/AP)

“They’re lucky to be alive.”

The teenager was known to police but was not on a terror watch list, Ms Webb said.

Australian Prime Minister Anthony Albanese said the boy was 16, adding that “there is no place for violence in our community”. Previously authorities had said he was 15.

The Christ the Good Shepherd in suburban Wakeley streams sermons online and worshippers watched as a person in black clothes approached the altar and stabbed the bishop and priest Isaac Royel during a church service on Monday evening before the congregation overpowered him, police said.

A crowd of hundreds seeking revenge gathered outside the Orthodox Assyrian church, hurling bricks and bottles, injuring police officers and preventing police from taking the teen outside, officials said.

The teen suspect and at least two police officers were also taken to hospital, acting assistant police commissioner Andrew Holland told journalists.

The church in a message on social media said the bishop and priest were in stable condition and asked for people’s prayers.

“It is the bishop’s and father’s wishes that you also pray for the perpetrator,” the statement said.

Mr Holland commended the congregation for subduing the teen before calling police. When asked if the teen’s fingers had been severed, he said the hand injuries were “severe”.

Australia Church Stabbings
The premier of New South Wales state, Chris Minns, described the scenes as ‘disturbing’ (Mark Baker/AP)

More than 100 police reinforcements arrived before the teen was taken from the church in the hours-long incident. Several police vehicles were damaged, Mr Holland said.

“A number of houses have been damaged. They’ve broken into a number of houses to gain weapons to throw at the police. They’ve thrown weapons and items at the church itself. There were obviously people who wanted to get access to the young person who caused the injuries to the clergy people,” he said.

Australians were still in shock after a lone assailant stabbed six people to death in a Sydney shopping centre on Saturday and injured more than a dozen others.

Mr Holland suggested the weekend attack heightened the community’s response to the church stabbing.

“Given that there has been incidents in Sydney the last few days with knives involved, obviously there’s concerns,” he said.

“We’ve asked for everyone to think rationally at this stage. We spoke to community leaders and members of the community to speak to their local people, to try and keep people calm.”

The premier of New South Wales state, Chris Minns, described the scenes as “disturbing” on social media and urged the community to remain calm and “stick together”. Religious leaders expressed shock and condolences.

Fairfield mayor Frank Carbone, leader of the neighbouring municipal government, described the bishop as a community leader.

“This is a very emotional situation. Obviously the community is very upset,” Mr Carbone told Sky News.

Christ the Good Shepherd had been preparing for Palm Sunday later this month.

The bishop, described in local media as a figure sometimes seen as divisive on issues such as Covid-19 restrictions, was in national news last year with comments about gender.

A video posted in May 2023 by the Australian Broadcasting Corporation about a campaign targeting the LGBTQ+ community showed the bishop in a sermon saying that “when a man calls himself a woman, he is neither a man nor a woman, you are not a human, then you are an it”.

He continued: “Now, since you are an it, I will not address you as a human anymore because it is not my choosing, it your choosing.”