The operation includes city, provincial and federal law enforcement officers.
Riot police, some with tactical gear, as well as mounted officers, held back dozens of protesters as they continue their demonstration against Covid-19 health restrictions.
“Protesters have put children between police operations and the unlawful protest site. The children will be brought to a place of safety,” the tweet said.
CNN has observed those children on the protest site in the last several days.
Local media showed live pictures of several arrests that occurred without incident. Police searches and arrests are taking place at a location less than a half-mile from the main protest site at Parliament Hill.
Debate in parliament on using the Emergency Act was slated to continue Friday, but the House of Commons will not be meeting because of police activity in downtown Ottawa, House of Commons Speaker Anthony Rota said in a statement.
Ottawa police on Friday confirmed the arrests of two protest organizers, Tamara Lich, 49, and Christopher John Barber, 46.
Lich was charged with counseling to commit the offense of mischief and Barber has been charged with counseling to commit the offense of mischief, counseling to commit the offense of disobeying a court order, and counseling to commit the offense of obstructing police.
Both are slated to make a court appearance on Friday.
Video posted on social media shows Lich interacting with a police officer, then being handcuffed and led away to a police cruiser.
Overnight, the three police forces hardened the perimeter in the downtown core, which includes checkpoints at on-ramps from highways and side streets.
About 150 protesters remain in the city’s downtown core, along with some 300 cars and trucks.
The secured area would ensure that those seeking entry for an “unlawful reason such as joining a protest cannot enter the downtown core,” according to interim Ottawa Police Chief Steve Bell.
With nearly 100 checkpoints, the perimeter encompasses most of Ottawa’s downtown area and is far larger than the protest footprint to date.
Those who live, work or have a lawful reason to be in the area would be allowed access, authorities said.
“We have a very deliberate plan that will be methodical and will take time for us to progress through to be able to completely remove anyone from the core. So what I can tell you is this weekend will look very different from the past three weekends,” Bell said Thursday.
“I’ll say it again, we want people to peacefully leave. But I can tell you that if they do not peacefully leave, we have plans, strategies, and tactics to be able to get them to leave,” he added.
Trudeau defends call for emergency powers
Officials have said a primary aim of invoking the Emergencies Act is to stifle funding to the demonstrators in Ottawa.
“These illegal blockades are being heavily supported by individuals in the United States and from elsewhere around the world,” Trudeau said. “We see that roughly half of the funding that is flowing to the barricaders here is coming from the United States. The goal of all measures, including financial measures in the Emergencies Act, is to deal with the current threat only, and to get the situation fully under control.”
The act, passed in 1988 and never before invoked, can temporarily suspend citizens’ rights to free movement or assembly. It can also provide for the use of the military, but Trudeau has said this would not be necessary.
“We did it to protect families and small businesses. To protect jobs and the economy. We did it because the situation could not be dealt with under any other law in Canada,” Trudeau said. “For the good of all Canadians, the illegal blockades and occupations have to stop, and the borders have to remain open.”
“The first act that he does when he has a chance to do something — he doesn’t go through step one, two, three — he goes straight to 100 and invokes the Emergencies Act,” Bergen told CTV News. “I don’t think anything that we will see will change our mind, we will be opposing it.”
The government must propose a motion in both the House and Senate explaining why federal officials need the powers and specifying what actions will be taken, then both the House and Senate must confirm the motions, according to CTV.
The federal government will work with premiers across the country “until the situation is resolved,” Trudeau said.
CNN’s Raja Razek, Chris Boyette, Amir Vera and Jenn Selva contributed to this report.