First, the shocking death of Warrant Officer Patrice Vincent, 53, in a targeted hit and run in Quebec.
Then, just two days later, an attack on the National War Memorial and Parliament Hill that left 24-year-old Cpl. Nathan Cirillo dead and shocked the country.
Here's a look back at how the week unfolded.
Two members of the Canadian Armed Forces were hit by a car in the parking lot of a commercial plaza in St-Jean-sur-Richelieu, Que., south of Montreal.
A dramatic chase with the suspect ensued, ending when the driver lost control of his car and flipped it into a ditch before being shot and killed by police.
“I was scared. I started crying," said witness Nathalie Vanasse.
"I wanted to get out of my car to go help, before the shots were fired … I saw a police officer jump to the side to protect himself. That's when I saw the suspect fall to the ground."
The hit-and-run attacker was identified as Martin Couture-Rouleau, a suspected extremist whose passport had been seized earlier this year.
The next day, the victim in Monday's attack was identified — Warrant Officer Patrice Vincent, a soldier for 28 years who had been considering retirement.
“When you lose a member of your family, especially in the Armed Forces, it's harder because you would like to be there," his cousin Sylvain Guerette told CBC News. "You would like to do something, but you can't.”
Guerette said Vincent’s family was hit hard by news of his death — particularly his mother and twin sister.
“He had a twin sister — they were the youngest in the family, so it's very hard for her."
A day of chaos erupted in Ottawa when a reservist guarding the National War Memorial was shot and killed by a masked gunman.
Moments later, witnesses reported as many as 50 shots being fired inside the Centre Block of the Parliament Buildings.
The first videos to emerge from the scene show law enforcement officers scrambling in the wake of the shooting.
CBC cameraman Jean Brousseau captured the chaos on video. Law enforcement officers are seen moving through an elegant hallway before a sustained volley of shots rings out. Startled witnesses are heard asking where they should seek cover.
It was later confirmed that gunman Michael Zehaf-Bibeau was shot dead inside the building by the House of Commons sergeant-at-arms and RCMP.
Confusion reigned for much of the afternoon as a swath of downtown Ottawa was placed under lockdown for hours and police released little information, refusing to say if they were looking for another gunman.
Slowly, eyewitness accounts — stories of terror and bravery — started trickling out of Parliament Hill.
Bystander Raivo Nommick said that "all of a sudden, I just heard a shot, turned around and there was a guy with a rifle .... and just pow pow.
"Then I saw one of the other Armed Forces guys just running. He barrelled over, just ran right over. The other guy just dropped. I looked back and just dived underneath and immediately called 911."
Prime Minister Stephen Harper and his Conservative MPs piled furniture against the door of their caucus room to prevent the gunman from entering and pinned themselves against the walls. Some even grabbed flagpoles to use as spears.
"We thought it was over," one source told CBC News.
"We couldn't tell good shots from bad shots," said another. "So the sheer number of shots could lead to a conclusion that the good guys lost the battle outside, and we were going to be rounded up and killed for being members of the government."
In the minutes after the shooting, MPs and parliamentary staff hailed Sergeant-at-Arms Kevin Vickers as a hero, reporting that he took the gunman down.
Justice Minister Peter MacKay tweeted, "Thank God for Sgt at Arms Kevin Vickers & our Cdn security forces. True heroes."
The soldier shot and killed at his post by the Tomb of the Unknown Soldier was later identified as Cpl. Nathan Cirillo, a reservist from Hamilton who had dreamed of becoming a full-time soldier.
Through tears, his uncle Jim Cirillo said the family was struggling to cope.
"For him to get shot and pass away — I don't know if life is fair … he didn't deserve that," he said. "I don't know how someone could have picked him out and do that."
Memorials to Nathan Cirillo popped up on Parliament Hill, at the Cirillo family home in Hamilton and at the Lieutenant-Colonel John Weir Foote Armoury in Hamilton.
Many Canadians woke up Thursday morning still reeling from the events of the day before.
An editorial cartoon by the Chronicle Herald's Bruce MacKinnon was hailed as an image that captured what many struggled to put into words.
The moving cartoon depicts the bronze statues from the National War Memorial leaning down to comfort Cpl. Nathan Cirillo.
Through the day, new photos began to circulate of the damage to the main building on Parliament Hill — images that gave some small insight into the harrowing scene that had unfolded there the day before.
But amid the horror, another story also emerged — the story of one woman who raced to save Cirillo's life and offer the soldier comfort in his final moments.
"I told him you are loved. You are brave. You are good," Barbara Winters, an Ottawa lawyer, told CBC Radio’s As It Happens.
"I said, 'Just think what you were doing when this happened. Just think, you were standing at the cenotaph. You were honouring others. Just think of how proud that would make your family. Your parents are so proud of you. Your family must love you so much.… Your military family loves you. Look at these people, we're all here helping you. We're all trying to do what we can for you. We all love you.'"
In the House of Commons, members of Parliament returned to work the day after scrambling for cover and barricading doors as gunshots rang out.
An emotional Vickers, the sergeant-at-arms who helped bring down the gunman, was honoured and given an extended standing ovation for his bravery.
Cirillo's body was transported to his home of Hamilton from Ottawa along the Highway of Heroes. As the motorcade moved across the province, well-wishers turned out to pay their respects, with at least one group singing the national anthem as the vehicles moved past.
The prime minister and the chief of the defence staff were out in Ottawa Friday to pay their respects to Cirillo and attend the return of ceremonial guards to the National War Memorial. The memorial had been without the standard ceremonial guards since Wednesday’s attacks.
The issue of policing and intelligence was also on the agenda Friday. CBC’s Louise Elliott reported that Public Safety Minister Stephen Blaney is "giving more indications of how the government intends to strengthen Canada's security laws in the wake of Wednesday's attack in Ottawa on Parliament Hill."
The procession is expected to arrive later Friday evening.
Share your condolences with the families of Cpl. Nathan Cirillo and Warrant Officer Patrice Vincent.