Nathan Cirillo

Classified by the RCMP as a terrorist act under the Criminal Code, it was the most serious security breach at Parliament Hill since the 1966 parliament bombing.

It took place two days after a man used his car to run over two soldiers in Saint-Jean-sur-Richelieu, Quebec, killing one.

The two incidents, which attracted international attention, raised concerns about the effectiveness of police actions to prevent terrorist attacks, the prevention of radicalization and the security measures in place at federal and provincial legislatures.

The Canadian government had already prepared a bill to expand the courtroom anonymity and surveillance powers of the Canadian Security Intelligence Service (CSIS), Canada's intelligence agency, which was due to be introduced the day of the shootings, and was postponed by the event.

Rouleau was a 25-year-old Québécois who became a Muslim convert in 2013 and was a supporter of the Islamic State of Iraq and the Levant (ISIL).

Rouleau used his car to run over the two soldiers before being fatally shot by police after an ensuing car chase.

Warrant Officer Patrice Vincent, age 53, subsequently died from injuries.

The terror threat level in Canada was on October 21 raised to medium in light of the ramming attack and due to "an increase in online 'general chatter' from radical groups including Islamic State and al-Qaeda."

In his address to the nation following the shootings on October 22, Prime Minister Stephen Harper referred to the October 20 incident as an ISIL-inspired terrorist attack.

Although both the October 20 and 22 attacks led to the death of Canadian soldiers, the Royal Canadian Mounted Police (RCMP) ruled out any direct connection between the attacks of October 20 and 22.

The 2014 shootings at Parliament Hill were a series of shootings that occurred on October 22, 2014, at Parliament Hill in Ottawa.

At the National War Memorial, Corporal Nathan Cirillo, a Canadian soldier and reservist on ceremonial sentry duty, was fatally shot by Michael Zehaf-Bibeau.

Described as mentally unwell, Zehaf-Bibeau then entered the nearby Centre Block parliament building, where members of the Parliament of Canada were attending caucuses.

After wrestling with a constable at the entrance, Zehaf-Bibeau ran inside and had a shootout with RCMP officers.

He was shot 31 times by six officers and died on scene.

Following the shootings, the downtown core of Ottawa was placed on lockdown and majority of schools in Ottawa were on lockdown while police searched for any potential additional threats.

The attacker, Michael Zehaf-Bibeau, was a 32-year-old Canadian habitual offender and addiction patient from Montreal.

He had been observed by acquaintances exhibiting erratic behaviour.

At the time of the shooting, Zehaf-Bibeau planned to leave Canada for the Middle East and was living in a homeless shelter in Ottawa while waiting for the processing of his Canadian passport application.

According to RCMP Commissioner Bob Paulson the "passport issue was central to what was driving" Zehaf-Bibeau.

Zehaf-Bibeau made a video prior to the attack in which he expressed his desire to "kill some soldiers" and his motives as being related "to Canada's foreign policy and in respect of his religious beliefs."

To acquaintances and co-workers, he had previously expressed support for jihadists and others in the Middle East resisting the West's intervention, but was not known to the police to be a terrorism risk.

In his mother's opinion, the attack was the "last desperate act" of someone with a mental disorder who felt trapped.

Canadian Muslim organizations condemned the attack.

On October 20, in the 2014 Saint-Jean-sur-Richelieu ramming attack, Martin Couture-Rouleau attacked two Canadian Armed Forces soldiers.

Shortly before 10:00 a.m. EDT, on October 22, 2014, witnesses saw Zehaf-Bibeau arrive at the National War Memorial carrying a rifle, which was later identified as a .30–30 Winchester Model 94 lever-action hunting rifle.

He was dressed in blue jeans and a black jacket, with a keffiyeh scarf over the lower part of his face.

He approached Corporal Nathan Cirillo of The Argyll and Sutherland Highlanders of Canada (Princess Louise's), a reserve infantry unit, who was one of three sentries from the Ceremonial Guard posted at the Tomb of the Unknown Soldier.

At close range, Zehaf-Bibeau shot Cirillo twice in the back, fatally wounding him.

Cirillo, like all others who have stood sentry at the memorial, carried an unloaded firearm, and had been provided by the CAF with no particular training for such a situation.

It was only minutes before the end of the sentries' shift, which ended at 10:00 a.m. Cpl. Kyle Button and Cpl. Branden Stevenson, two other soldiers on sentry duty, attempted to stop Zehaf-Bibeau, but they were shot at by him and forced to flee to the other side of the Memorial.

Zehaf-Bibeau then pulled down his scarf, held his rifle one-handedly over his head and yelled, "For Iraq."

Cpl. Anthony Wiseman, who was nearby, then attempted to stop Zehaf-Bibeau, but Zehaf-Bibeau attempted to run him over.

The three soldiers then attended to Cirillo.

Along with bystanders, they applied first aid to Cirillo, attempting to resuscitate him, before Paramedic Chief Anthony DiMonte was first on scene, assumed patient care until additional paramedics arrived to provide medical care before Cirillo was taken to hospital.

Meanwhile, Zehaf-Bibeau returned to his vehicle, a small grey Toyota car, which was parked on the south side of Wellington Street behind the memorial, and drove west along Wellington a short distance to Parliament Hill, where he abandoned his vehicle.

Past scattering bystanders, he ran through a gate in the fence surrounding the Parliament Hill precinct and carjacked a parliamentary vehicle assigned to ministers of the Crown, which he drove to the Centre Block parliament building.

The government introduced new anti-terrorism measures with the Anti-terrorism Act, 2015, and creating the Parliamentary Protective Service to guard the parliament grounds.

Security at Parliament Hill is to be stepped up.

On June 3, 2015, it was reported that "RCMP officers have started openly carrying submachine guns on Parliament Hill as part of a visible increase to Parliament Hill security."