“We believe there are elements that are satisfied in terms of religious motivated extremism,” she said.

Under NSW laws, once a terrorism designation is made by the police commissioner and affirmed by the police minister, officers are granted special powers to investigate an attack that has taken place.

Police, without requiring a warrant, can stop and search people and vehicles, demand the disclosure of people’s identities, enter and search premises and vehicles, or establish a cordon such as a roadblock around a target area.

After the attack on Monday night, a large crowd that gathered outside the church became hostile to police, Webb said.

“People used what was available to them in the area, including bricks, concrete pilings, to assault police and throw missiles at police and police equipment, police vehicles,” she said.

Injured police were taken to hospital. Twenty police vehicles were damaged, 10 of which are now unusable.

“This is unacceptable,” Webb said. “Police attended the incident in Wakeley last night to assist that community in response to calls for assistance. And the crowd turned on police.”

The commissioner said rioters would be prosecuted.

Premier Chris Minns called for calm and respect for the law during a “major, major terrorism investigation”.

“It’s my great plea to everybody in Sydney to heed those calls from the NSW Police, the government and major religious leaders – Islamic leaders, Christian leaders – united last night with one simple message: remain calm and please follow police directions,” Minns said.

NSW Ambulance Commissioner Dominic Morgan said paramedics responded to 30 patients over a period of about 3½ hours. Morgan said the crowd numbers grew to include hundreds of people in a “rapidly evolving situation”.

“Our paramedics became directly under threat, supported by police, and had to retreat into the church,” Morgan said. Paramedics were “holed up” in the church for more than three hours, he added.

“Six of our paramedics could not leave that facility for fear of their own safety from the community that they serve,” Morgan said.

In a press conference on Tuesday morning, Prime Minister Anthony Albanese said there was “no place” for extremism in Australia.

“Last night, a 16-year-old who has been apprehended was accused of stabbing a bishop at Christ The Good Shepherd church in Wakeley. This is a disturbing incident,” he said.

“There is no place for violence in our community. There’s no place for violent extremism. We’re a peace-loving nation. This is a time to unite, not divide, as a community, and as a country.”

Albanese, flanked by ASIO director-general Mike Burgess and AFP commissioner Reece Kershaw, said there had been a national security committee meeting this morning to discuss the attack, which has been declared a terror incident.

Loading

“Can I say that we understand the distress and concerns that are there in the community, particularly after the tragic event at Bondi Junction on Saturday. But it’s not acceptable to impede and injure police doing their duty, or to damage police vehicles in a way that we saw last night,” Albanese said.

“People should not take the law into their own hands. But should allow our police, and our security agencies, to do their job. My job as prime minister is to give them that support.”

Kershaw said Monday night’s attack in western Sydney was being investigated by the NSW joint counterterrorism team, which includes the AFP.

“The AFP, together with ASIO and NSW Police, will continue to investigate how this incident occurred, and the individual involved,” he said.

Opposition Leader Peter Dutton, speaking at a press conference in Perth, condemned the attack and said he had written to the prime minister, offering the opposition’s support to the government in its response to the incident.

“It doesn’t matter if you disagreed vehemently with a priest, a rabbi, with any person, violence is never the answer,” Dutton said.

Graphic footage captured on a livestream of last night’s sermon showed Bishop Emmanuel speaking at the altar of the church as a male wearing a black jumper walked towards him and pulled out an implement.

As horrified churchgoers screamed and ran to safety, the male stabbed the priest in the chest. The priest then fell to the floor and was stabbed a further five times as worshippers rushed towards him and managed to separate the assailant from the priest.

Video taken in the aftermath of the stabbing shows the bishop on the floor as parishioners hold bandages against his head. Other footage showed the attacker smiling as he was held to the floor by a police officer.

Federal MP for Fowler Dai Le, whose south-west Sydney electorate includes the Christ The Good Shepherd Church, said she feared the declaration of terrorism would fuel fear in the community.

“I’m not exaggerating, I feel sick in the stomach that the premier has done that. But I hope he has a good reason to do this,” she said on ABC News Breakfast.

Earlier she said the church is one of seven Assyrian churches that are much loved in the community.

“[They have] participated in activities in terms of handing out food and presents to the community and over the years,” she said.

Asked whether the bishop’s sometimes controversial statements could have played a role in the attack, Le said people should not jump to conclusions.

“I would caution people [not] to jump to …. any kind of interpretation conclusion about what the motivation behind it [is] before the police run their work,” she said.

One of Sydney’s most prominent Islamic houses of worship will have extra security for the coming week, after threats were made on Monday night to firebomb Lakemba Mosque.

“We had close to 500 people here. Unfounded, but there were threats to firebomb the mosque. We don’t want to perpetrate that, we’re vigilant,” Gamel Kheir, secretary of the Lebanese Muslim Association told reporters on Tuesday.

Lakemba Mosque Imam Jamal-Ud-Din El-Kiki said: “We pray for the bishop’s recovery. We hope that we can recover from this as an Australian community.”

El-Kiki said tensions were running high in the Muslim community and he was wary of the designation of a terrorist incident.

“I think it’s a politically loaded term, I’m concerned about this being treated as a Muslim problem. I think it’s about a teenager who had a knife who decided to commit a horrific action.”

The Australian National Imams Council said it and the Australian Muslim community “unequivocally condemns” the attack on the bishop.

“These attacks are horrifying and have no place in Australia, particularly at places of worship and towards religious leaders,” the organisation said in a statement.

“We urge the community to stay calm and work together towards the safety and security of Australians.”

Faith NSW chief executive Murray Norman said an attack on one faith was an attack on all, and that faith communities stood unified against hate and violence.

“During a week of mourning where we have seen the worst of humanity on display, this is yet another sobering reminder that we all need to do more to stamp out this vile conduct from our state,” he said.

“Incidents such as these will only strengthen our resolve and we will emerge stronger and more united.”

with Rachel Clun, Perry Duffin, Michael McGowan, Paul Sakkal, Matthew Knott, Clare Sibthorpe

Our Breaking News Alert will notify you of significant breaking news when it happens. Get it here.