Police in Toronto have shot and killed a man after he was spotted carrying a rifle near an elementary school, prompting an emergency lockdown for hundreds of students.

Officers responded to reports of a man, described as being in his late teens or early 20s, carrying a firearm in Scarborough’s Port Union area of the Canadian city about 1pm.

Witnesses told local media they heard three gunshots and then saw police attempting to revive the man.

The police chief, James Ramer, told reporters Thursday afternoon that the event was “isolated” and there was no further threat to public safety, but that police would increase patrols in the area.

“Due to the proximity to a school, I certainly understand the trauma and how traumatic this must have been for staff, students and parents, given the recent events that have happened in the United States,” he said.

The scare comes as the US reckons with its worst school shooting in a decade. Two days ago, 19 children and two teachers were killed when an 18-year-old gunman entered an elementary school in Uvalde, Texas.

Ramer said he was unable to comment further on the incident because the province’s Special Investigations Unit will conduct an investigation.

The police watchdog intervenes whenever an officer fires at or kills a civilian.

The Toronto district school board said two schools – Charlottetown Junior public school and Centennial Road Junior public school – went into “hold and secure” mode. Two other schools – Joseph Howe Senior public school and Sir Oliver Mowat Collegiate Institute – went into lockdown.

A spokesperson for the school board said it didn’t appear a nearby school was linked to the incident.