Arrests have been made at two demonstrations outside a synagogue in Thornhill, York Regional Police say.

YRP spokesperson Sgt. Andy Pattenden confirmed the arrests to CTV News Toronto but did not provide further details about how many were apprehended and what prompted police to take them into custody.

"York Regional Police will conduct a thorough investigation into any criminal incidents. We encourage residents and protesters to keep the peace and act in a lawful manner," Pattenden said in an email statement.

Thursday's demonstration was the third to take place near the synagogue on Clark Avenue West and York Hill Boulevard.

Two duelling groups – one carrying Palestinian flags and the other holding Israeli flags -- were seen lining up the opposite sides of the street with officers standing in between them to keep them separate.

Chopper 24 captured a scuffle between several members of the two groups but was quickly broken up by officers.

Vaughan Mayor Steven Del Duca said Thursday morning that police have a plan in place to ensure order ahead of the protest.

The synagogue, in the area of Bathurst Street and Clark Avenue in Vaughan, was the site of another protest yesterday as well as one over the weekend which resulted in one person being charged for allegedly bringing a nail gun.

Pro-Palestinian activists have taken issue with an event at the synagogue for those interested in buying real estate in Israel. The activists claim that the event includes the promotion of real estate purchases in the West Bank — land Israel captured from Jordan in 1967 and which the Palestinians want for a future state. Organizers have denied that.

A joint statement issued by elected representatives for the area Thursday said many community members are deeply concerned about the protests at the synagogue.

"We share these concerns. It is unacceptable that a place of worship, or nearby schools and day cares, be targeted in this way," read the statement, which was jointly signed by Vaughan Mayor Steven Del Duca, MP Melissa Lantsman, MPP Laura Smith and local councillor Gila Martow.

"The right to peaceful protest is an important freedom afforded to all Canadians. But this freedom does not give people the right to incite hate, make threats or engage in acts of violence."

The statement said that York Regional Police have an operational plan for the day in order to protect all residents and maintain order at the synagogue, as well as at a nearby community centre.

In a statement ahead of the protest, the Centre for Israel and Jewish Affairs said the protests are part of a "campaign of harassment and intimidation" aimed at the city's Jewish community.

"The motive behind these protests is clear—to target and intimidate the Jewish community," the statement read. "While freedom of opinion and speech are fundamental in a democratic society, violence, harassment, and intimidation unequivocally cross the line."

The group is calling for provincial legislation that would guarantee safe access to "institutions serving vulnerable members of racialized, ethnocultural, and religious communities, including places of worship, community centres, schools, and hospitals."

Another protest several weeks ago drew sharp criticism from the medical community when protesters climbed on top of Mount Sinai Hospital in downtown Toronto. The protesters claimed they were on their way to a larger protest at the Israeli consulate and were not actively targeting the hospital, which has strong affiliations with the Jewish community.

Trudeau says some of the protests have crossed a line

Meanwhile, Prime Minister Justin Trudeau said people have a right to express their "anguish" and to protest around the Israel-Hamas war, but when protests turn to harassment of fellow citizens, "there's a line that's crossed."

"Canadians have a right to protest, absolutely; to make their anguish, their anger, heard by other Canadians. That's important too. We will always protect that right. But when the protests turn to hatred, or to harassment, particularly against fellow Canadians, there's a line that's crossed," Trudeau said.

The Prime Minister made the comments during a scrum with reporters at an unrelated event at Women's College Hospital in downtown Toronto Thursday. He was asked about the many ongoing protests which have taken place in Toronto, including one last week which forced the cancellation of an event he was scheduled to attend with the Italian prime minister at the Art Gallery of Ontario.

Trudeau said that while "nobody can remain indifferent to the suffering and the anguish going on in Gaza right now," he's also heard from many people who feel targeted and harassed by the protests, which have sometimes taken place at Jewish-owned businesses, community centres and synagogues.

"I've heard from too many members of the Jewish community particularly, who are seeing their synagogues or community centres, their neighborhoods protested," Trudeau said. "People feel unsafe in their own country. I know Canadians have very strong feelings about this conflict, and rightly so – they're horrible things that we're seeing – but it is not who we are to take it out on our fellow Canadians."

He added that "hateful or harassing behavior, particularly against neighbors, is not what we do here in Canada."

-          With files from The Canadian Press