Last weekend, a man went on a shooting rampage in Nova Scotia, Canada, killing at least 16 people, including one police officer. This is the worst active shooter incident in Canadian history.

The active-shooter incident began in the late hours of Saturday.

The Royal Canadian Mounted Police (RCMP) has identified Gabriel Wortman, aged 51, as the perpetrator. He had disguised himself as a police officer and even drove a near-replica of an RCMP car during his attack.

The shooter appears to have specifically selected his first victims but then went on a complete rampage shooting random people on sight. The RCMP found the first victims inside and outside of a house in the town of Portapique, which is located about 60 miles north of Halifax, the provincial capital of Nova Scotia.

After a manhunt, that took several hours, the shooter was killed by law enforcement officers outside a gas station approximately 25 miles south of Halifax.

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The vehicle used by the shooter. RCMP warned people to avoid it if they saw that particular identification number. For many, however, it was already too late (Image courtesy of RCMP).

“I never imagined when I went to bed last night that I would wake up to the horrific news that an active shooter was on the loose in Nova Scotia,” said Nova Scotia Premier Stephen McNeil. “This is one of the most senseless acts of violence in our province’s history.”

Although the attack was clearly premeditated, as shown by the shooter’s preparations, the motives behind it are still unknown.

“As a country, in moments like these, we come together to support one another. Together we will mourn with the families of the victims, and help them get through this difficult time,” Prime Minister Justin Trudeau said in a written news release statement.

Constable Heidi Stevenson, a mother of two, was killed while responding to the incident. The Nova Scotia RCMP Commanding Officer, Assistant Commissioner Lee Bergerman, paid a tribute to her in a statement:

“It is with tremendous sadness that I share with you that we lost Cst. Heidi Stevenson, a 23-year veteran of the Force who was killed this morning, while responding to an active shooter incident. Heidi answered the call of duty and lost her life while protecting those she served. Earlier this afternoon, I met with Heidi’s family and there are no words to describe their pain. Two children have lost their mother and a husband his wife. Parents lost their daughter and countless others lost an incredible friend and colleague.”

Constable Heidi Stevenson.

The last mass shooting of similar magnitude in Canada took place in 1989 when a gunman killed 14 people in Montreal’s Ecole Polytechnique.

To purchase a handgun or assault rifle in Canada you must have a license and register it — before the 1989 shooting you didn’t have to register it. You must also undergo basic firearms training; authorities also conduct a thorough background check before you’re greenlighted.