With prayers, protests, and a heavy police presence, Canada has marked the anniversary of the Oct. 7, 2023, attack by Hamas on Israel that killed about 1,200 people and triggered an ongoing war.

Children arrived at Jewish schools under police watch in cities including Vancouver and Toronto.

Mourners remembered victims of the attacks and prayed for the safe return of hostages seized by Hamas, while others demonstrated against Israel鈥檚 military action in Gaza that has killed more than 41,000 Palestinians, according to the territory鈥檚 health ministry.

Events were mostly trouble-free, but in Montreal, what began as a large and peaceful pro-Palestinian march through the city鈥檚 downtown ended with police using chemical irritants and sheer numbers to chase off a group of protesters who used metal bars to smash the doors and windows of a row house under construction belonging to McGill University.

A masked speaker with a megaphone said it was to be part of a sports science institute named after Israeli-Canadian billionaire Sylvan Adams, and urged the protesters to 鈥渢ake out your rage on the building.鈥�

For the past year, the Hamas attack and the ensuing war have been at the heart of widespread protests, university encampments, and a spike in reports of hate crimes against Jews and Muslims.

In Montreal, several hundred people had gathered downtown to mark the anniversary with speeches, wreath-laying and prayers while a smattering of pro-Palestinian protesters shouted and police kept watch.

Channa Leah Natanblut, a Concordia student and one of the speakers, said Jews were hurting and mourning and it was important to deal with that sadness and show strength.

鈥淚t鈥檚 been a very hard year, but I think it鈥檚 important to show other Jews that we are not intimidated by the violence we鈥檝e seen in the streets of Montreal 鈥� their fear tactics are not working on us,鈥� Natanblut said.

In the separate protest march from Concordia University to McGill, some protesters ran down a side entrance onto the closed off McGill campus, knocking down a metal barricade manned by campus security.

That group was confronted by a contingent of police on horseback, before being chased back off campus by police who ran at them, banging batons on shields.

At the beginning of the march, McGill student Rama Al Malah said students were there to commemorate one year since the beginning of what she called a 鈥渕ass genocidal campaign against the people of Gaza.鈥� She said student protesters wanted to reaffirm their support for Palestinians and reiterate demands to Concordia and McGill, including divestment from companies linked to Israel鈥檚 war effort and an academic boycott of Israeli institutions.

Thousands of supporters of Israel gathered in Toronto鈥檚 north end Monday night, many of them holding photos of hostages or waving small Israeli flags.

Mayan Shavit, who lost two members of her family, an aunt on Oct. 7 and a cousin who was among six hostages killed in August, said she was in 鈥渄isbelief鈥� seeing so many people at the event.

鈥淎 year ago on Oct. 7, 2023, we woke up to a completely upside-down world,鈥� she said. 鈥淚 don鈥檛 know to what world we woke up to, but it wasn鈥檛 the world we all knew.鈥�

Jeff Rosenthal, the chair of United Jewish Appeal-Federation of Greater Toronto, thanked local officials who attended the event, including Premier Doug Ford.

鈥淭onight, we come together to reflect and to remember the lives that were lost, the communities that were shattered one year ago and those remaining hostages that we so desperately want back home.鈥�

The mother of a Montreal man killed in the Oct. 7 Hamas attacks told a gathering in that city that the events of the last year have given her family the chance to see both the best and the worst of humanity.

Raquel Look said her 33-year old son Alexandre Look died a hero while shielding others after the music festival he was attending came under attack.

鈥淚 know that Alex infused my soul with the strength to keep going, and I will work tirelessly to build a future based on peace and co-operation for all people,鈥� she said.

Long lines formed outside a Vancouver synagogue as people attending a memorial gathering had to go through metal detectors and were scanned by security wands.

Politicians of every stripe attended the event, including NDP Leader David Eby and B.C. Conservative Leader John Rustad, who are midway through an election campaign.

Police in major cities stepped up protections during the anniversary.

Children were dropped off by parents at the Talmud Torah elementary school in Vancouver Monday morning under the gaze of police in bulletproof vests and at least one police dog.

Allie Saks, who has two children attending Talmud Torah, broke down in tears when asked about the police presence and parents鈥� unease.

鈥淚t鈥檚 hard to drop your kid off somewhere where you have to see police in front,鈥� Saks said. 鈥淎nd it鈥檚 emotional for all of us. We鈥檙e all in a state of grief today and for the whole year 鈥� until our hostages come home.鈥�

Vancouver Police Chief Const. Adam Palmer said last week that protests posed a 鈥渟ignificant鈥� risk of disorder on Monday, and officers trained specifically for large-scale events were being deployed.

Pro-Palestinian group Samidoun was planning a Vancouver rally which it promoted by referring to the Oct. 7 attacks as 鈥淎l-Aqsa Flood,鈥� the Hamas code name for the operation.

A Toronto police van was parked out front of a Hebrew day school along Bathurst Street in one of the city鈥檚 most recognizably Jewish neighbourhoods. On the corner, a large poster called for the return of hostages.

Just up the road, at the Sherman Campus, a sprawling hub of Jewish groups and agencies, preparations were being made for a memorial event planned for Monday night.

A spokesperson for the UJA Federation of Greater Toronto, which was hosting the evening event, said it was important to gather to 鈥渞emember all the lives that were tragically lost on Oct. 7 in Israel, but also to recognize that this situation is still a live situation.鈥�

鈥淭his is not an opportunity where we are remembering something that happened. We still have more than 100 hostages, including family members of Canadians, who are in Gaza being held by Hamas,鈥� said Sara Lefton, the organization鈥檚 chief development officer.

Some victims鈥� families also launched legal action on Monday over the attack.

Tiferet Lapidot鈥檚 father, along with another Canadian who lost family members in the attack, filed a claim in Ontario Superior Court seeking $250 million in damages under Canada鈥檚 Justice for Victims of Terrorism Act, plus an additional $100 million.

The claim lists Hamas, various Palestinian organizations, the leaders of Iran and Syria and several Canadian individuals and groups among the defendants.

It alleges all the defendants are in some way responsible or liable for the losses and damages caused by the deaths. None of the allegations have been tested in court.

Family members said the last time they heard from Lapidot was in a phone call from the Supernova music festival near Israel鈥檚 border with the Gaza Strip, where Hamas launched its attack.

鈥淪he called her mother at nine o鈥檆lock in the morning, telling her that she loves her and they鈥檙e shooting youngsters all around,鈥� her uncle, Harel Lapidot, said Monday at a Toronto event marking the anniversary.

A year later, the family鈥檚 grief over the loss of the young woman he described as their 鈥渟unshine鈥� is 鈥済etting worse day by day,鈥� her uncle said. She was one of at least eight people with ties to Canada who died that day.

鈥淚t was the most horrific thing for us as a family to lose Tiferet. Tiferet was a happy young lady 鈥� that was just dancing at a festival,鈥� he said.

Prime Minister Justin Trudeau told an event in Ottawa that members of the Jewish community in Canada continue to feel the effects of Oct. 7, including when people wave the flags of Hamas and Hezbollah and fellow Canadians dismiss their pain.

鈥淵ou relive it when the term Zionist is tossed around as a profanity, a label for something other than what it truly means, believing in the right of Jewish people, like all people, to determine their future,鈥� he said.

Conservative Leader Pierre Poilievre also addressed the crowd and criticized the government鈥檚 positions on the war and its handling of protests and attacks on Jewish institutions.

鈥淭his ideology that seeks to divide our people based on race and ethnicity that has led to these horrifying outbursts of hatred are not from the bottom up. They are from the top down,鈥� he said.

Monday鈥檚 events took place against a backdrop of escalating hostilities in the Middle East.

Hamas, which remains in control of the bombarded Gaza Strip, marked the anniversary by firing a barrage of rockets at Tel Aviv.

Lebanon鈥檚 Hezbollah vowed to keep up its own rocket fire despite recent losses in southern Lebanon, where Israel has been mounting a ground incursion.