CANADA’S WORST MASS shooting started as a domestic dispute between the gunman and his girlfriend, who survived the attack, a police official has said.

The official confirmed to The Associated Press that the weekend rampage in Nova Scotia erupted after an argument between the pair.

The official, who spoke on condition of anonymity, said more details would be provided at a news conference today. 

Police have said 51-year-old Gabriel Wortman acted alone in waging a shooting spree that killed at least 22 people across northern and central Nova Scotia.

There are 16 crime scenes in five different rural communities throughout the province.

The suspect was shot dead on Sunday morning, about 13 hours after the attacks began.

Several bodies were found inside and outside of one house in the rural town of Portapique, police said.

Bodies were also found in four other communities, and authorities believe the shooter targeted his first victims but then began attacking randomly as he drove around.

Police have said Wortman carried out much of the attack disguised as a police officer in a vehicle marked to seem like a patrol car.

They say he shot people in and around their homes and set fires to homes in Portapique.

Wortman, who owned a denture practice in the city of Dartmouth, near Halifax, lived part time in Portapique, according to residents.

Atlantic Denture Clinic, his practice, had been closed the past month because of the coronavirus pandemic.

Authorities said Wortman did not have a police record, but information later emerged of at least one run-in with the law.

Nova Scotia court records confirm he was ordered to receive counselling for anger management after pleading guilty to assaulting a man in the Halifax area on 29 October 2001.

Mass shootings are relatively rare in Canada.

The country overhauled its gun control laws after Marc Lepine shot 14 women and himself to death at Montreal’s Ecole Polytechnique college in 1989.

Before the weekend rampage, that had been Canada’s worst mass shooting.