NSW election campaign marred by 'terrifying' violence

Two people have been charged after "disgraceful" pre-election violence erupted in Sydney when LGBTQI+ activists were attacked outside a church before a speech by NSW One Nation leader Mark Latham.

A 34-year-old man was charged with encouraging the commission of crimes, while a 41-year-old man was charged with assault following the violent scenes outside St Michael's Church, Belfield in the city's southwest on Tuesday night. 

Mr Latham had been invited to speak at the church about parental rights ahead of Saturday's state election.

The One Nation leader and LGBTQI+ activists have previously clashed over gender issues, with Mr Latham pushing for laws banning the discussion of gender diversity in NSW classrooms.

Footage posted to Facebook by Community Action for Rainbow Rights, a Sydney-based LGBTI+ activist group, showed its members being punched as they were shielded by police on the street. 

One man is wearing a T-shirt that reads 'All Christian Lives Matter', a slogan linked to a pro-Christian activist group in Sydney.

Riot squad and other officers were called in to stem the violence and disperse the crowd of around 250 people after police protected the LGBTQI+ activists who had bottles and rocks thrown at them, NSW Police Superintendent Sheridan Waldau said on Wednesday.

"A group of protesters - of about 10 people - were in the vicinity of Margaret Street, where the church was, when a mob of about 250 people from the event rushed down the street," she told reporters.

"We believe the people involved in the violent confrontation were attending the event that was to be held at the church hall.

"We were able to push the protesters into a police vehicle and move them safely from the scene of the incident."

Police expect more charges to be laid.

A glass bottle struck a male constable who was taken to hospital in a stable condition with an injured hand, while a 38-year-old man was pushed to the ground and assaulted.

A Community Action for Rainbow Rights spokesperson, who wished to remain anonymous, said members feared for their lives.

"It was obviously terrifying. I've been an activist for more than a decade and I've never seen that far-right violence up close and personal like that," the spokesperson told AAP.

The Catholic Archdiocese of Sydney also condemned the incident, saying those who acted violently outside the church were not members of the local parish community.

"Violent acts towards anyone is incompatible with the Gospel and never acceptable. For Christians and for all Australians, the events that occurred last night do not represent who we are and must be condemned," a spokesperson for the archdiocese told AAP.

Mr Latham gave his speech at the church, despite the violent scenes outside.

"To not give my speech, to go straight home would have allowed the transgender protesters to cancel my free speech and democratic rights as an election candidate, things that are sacred to me and have been for 35 years in running for elections, local, federal and state," he tweeted.

"No one should take the law into their own hands. Violence at political events is wrong."

Premier Dominic Perrottet labelled the violence "disgraceful", saying it was an aberration on an election campaign run in "great spirit".

"There should be a sense of respect and tolerance towards people with different views," he told reporters.

Labor leader Chris Minns described the violence as unfortunate, saying he would "love to see a campaign where there are no scenes, where people can get the views out to the people of NSW to make their calls".

Independent Sydney MP Alex Greenwich said "a small but loud group" of "cruel and lazy politicians" were targeting the LGBTQIA+ community.

"They are a disgrace and all major party political leaders should call it out and condemn it," he said.