Ottawa: Four people were killed when a gunman stormed a high school in a remote western Canadian town Friday, police said, revising down an earlier death toll.

Prime Minister Justin Trudeau had said five people were killed and two were critically injured.

‘At 1:47 pm (1947 GMT), one male was taken into custody outside of the school and a firearm was secured,’ Royal Canadian Mounted Police superintendent Maureen Levy told a press conference.

‘Initial information was that there were five deaths as a result of this tragedy. At this time, I can confirm that four individuals are deceased,’ Levy said.

Authorities would not reveal the identities of the victims while their investigation is still ongoing, she said.

‘In addition to those confirmed deceased, a number of people have been injured,’ Levy added, saying the type and extent of their injuries was unknown.

Levy said police responded after receiving an emergency call about ‘a person discharging a weapon in the community.’

Investigators, she said, have also secured a second possible crime scene in the town of La Loche, near the high school.

Students had reported hearing six or seven shots ring out shortly after 1:00pm.

Several witnesses reported seeing a ‘boy,’ who was either a student or someone who formerly attended the school, opening fire inside the building.

The school shooting is the deadliest in 26 years in Canada.

On December 6, 1989, a 25-year-old man opened fire at Polytechnic School in Montreal, killing 14 people including 10 female students.

Unlike in the United States, such shootings are rare in Canada where firearms are more regulated than they are south of the border.