LONDON, Ontario: Prime Minister Justin Trudeau joined several thousand mourners in a vigil Tuesday evening to remember three generations of a Canadian Muslim family killed in what police said was a premeditated hate crime, as a grieving community stood united in the midst of the crisis.

"This is our city," Bilal Rahhal, chair of the London Muslim Mosque, told the crowd. "Never allow anyone to make you think otherwise because of the color of your skin, your faith, or where you were born. ... This is our city and we're not going anywhere."

On Sunday, four members of the family were killed as they were out on an evening walk near their home in London, Ontario, when police say a man rammed them with his pick-up truck, targeting them because of their religion.

The victims were Salman Afzaal, 46; his wife, Madiha Salman, 44; their 15-year-old daughter, Yumna Afzaal; and Afzaal's 74-year-old mother. Their 9-year-old son, Fayez Afzaal, remained hospitalized on Tuesday with serious but non-life-threatening injuries in stable condition.

Nathaniel Veltman, 20, has been charged with driving a pickup truck onto a curb and hitting the family in London, a city of over 400,000 people located 200km (124.27 miles) southwest of Toronto.

He was arrested on Sunday just a few hundred meters from the London Muslim Mosque, which the Afzaal family attended and where Tuesday's vigil was held.

Addressing the mourners, Trudeau said his government would take action, after placing flowers on the steps of the mosque, without giving details.

"This was an act of evil. But the light of the people here today, the light of the lives of the Afzaal family – that will always outweigh the dark," Trudeau said.

The majority of people attending wore masks, after the Ontario government made exception to COVID-19 restrictions to allow the vigil to take place.

Canada's opposition leader, Erin O'Toole, other political leaders including NDP leader Jagmeet Singh, the first person of color to lead a federal political party in Canada, and Ontario Premier Doug Ford were also in attendance.

The attack has caused a nationwide outpouring of grief, with similar vigils taking place in Toronto, Vancouver and other cities across Canada.

The #OurLondonFamily hashtag had almost 10,000 tweets posted of Tuesday evening, and many on social media changed their avatars to an image posted by the London Muslim Mosque of four white outlines of the victims on a purple background with a green ribbon.