Police say the family members killed were a 74-year-old woman, a 46-year-old man, a 44-year-old woman, and a 15-year-old girl, the CBC reports. A nine-year-old boy was in hospital with serious but non-life-threatening injuries, said police.
"There is evidence that this was a planned, premeditated act, motivated by hate", Detective Superintendent Paul Waight of the London, Ontario, police department told reporters. The family requested the names not be released.
"It is believed that these victims were targeted because they were Muslim..."
The incident happened on Sunday evening when a truck plowed into the group of pedestrians. The two adults and one teenaged child succumbed to their injuries at hospital.
A man, woman and teenager were taken to the hospital and later died.
He was arrested in a mall parking lot without incident while wearing a body-armor-type vest, police said. They also said the suspect didn't know the family.
"Investigators believe that this was an intentional act and that the victims were targeted due to their Islamic faith", a statement from police in London, Ontario, said on Monday.
"Hate and Islamophobia have NO place in Ontario", tweeted Ontario Premier Doug Ford. My thoughts and prayers are with the families and friends during this hard time. "These heinous acts of violence must stop".
Canada is generally welcoming toward immigrants and all religions, but in 2017 a French Canadian man known for far-right, nationalist views went on a shooting rampage at a Quebec City mosque that killed six people.
Prime Minister Justin Trudeau told Muslims in London, Ont. and across the country today that his government stands with them after four members of a Muslim family there were killed in what police described as a targeted hate crime. "Let me be clear, this was an act of mass murder perpetrated against Muslims, against Londoners, and rooted in unspeakable hatred", he said.
"An Islamophobic act of terror like this has no place in Canada", O'Toole said on Twitter.
Just prior to the attack, Alek Minassian posted on Facebook a reference to an online community of "involuntary celibates" whose sexual frustrations led them to embrace a misogynist ideology. He has been charged with four counts of first-degree murder and one count of attempted murder. I grieve for their loved ones. Police said a black pickup truck mounted a curb and struck the victims at an intersection.
"I was shaken up, thinking it was an erratic driver", Martin said.
First responders in full sprint, a police officer performing chest compressions on one person and three others down on the ground.
"I'm still in shock", said Martin visibily emotional.