Chief of the Defence Staff Gen. Tom Lawson says the Canadian Forces "will not be deterred" by the attack in Ottawa that left a 24-year-old reservist dead, but some security change have been made at military sites and members are under orders to limit when and where they wear their uniform.

Cpl. Nathan Cirillo, 24, died Wednesday after being shot while guarding the National War Memorial in Ottawa. The attack followed the death of Warrant Officer Patrice Vincent, 53, who died after being struck by a car in a hit and run in Quebec.

"Let me be clear. We will not hide. We will not be deterred nor intimidated from our duties," Lawson said Thursday afternoon. He said the two men were "both killed in cold blood for no other reason than they were serving their country."

RCMP Commissioner Bob Paulson said earlier in the day that there was no evidence of a link between the two attacks.

Ottawa Shooting 20141023 TOPIX

Ottawa Police officers move flowers to an area in front of the National War Memorial near Parliament Hill , where Cpl. Nathan Cirillo, 24, was killed by a gunman in Ottawa. (Justin Tang/Canadian Press)

Lawson said Thursday that members of the Forces have been ordered to "minimize unnecessary exposure" regarding their uniforms in public — meaning they can go to or return from work in uniform but are being told not to wear their uniform during off-duty activities like shopping or eating out.

The directive, a copy of which was obtained by The Canadian Press, also includes dress uniforms. It follows not only the Ottawa shooting, but Monday's tragedy in Quebec, where one soldier was killed and another was injured when they were struck by a car driven by a man who had been "radicalized", law enforcement officials said.

He said officials are assessing security measures for soldiers and military sites and considering whether adjustments need to be made.

The shooting unfolded very quickly Wednesday morning, with the shooter moving from the war memorial to Centre Block.

Lawson told gathered reporters he was in the Langevin Building Wednesday, just across the street from Parliament Hill, when the alarm went off, and he said his driver actually gave chase to the shooter leaving the war memorial. 

He said the military will strive to balance full protection of members with the public's need to see them.

"We know that Canadians stand with us in condemning these two hateful attacks," he said.

Flags at half-mast

A day after the shooting, the flag on all federal buildings and establishments in the country, including the Peace Tower in Ottawa, were at half-mast. On Thursday, staying vigilant and being aware of heightened security were the main messages to Canadians from authorities.

"We will be vigilant and we will not run scared. We will be prudent but we will not panic," Prime Minister Stephen Harper said. "Terrorism has been here with us for a while and dangerously close on a number of occasions. Our laws and police powers need to be strengthened in the area of surveillance, attention and arrest." 

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"We're ever vigilant on potential threats and ask the community to remain vigilant as well," said Ottawa police Chief Charles Bordeleau. "We're seeking help from the community — if they have any information that leads us to believe that there are potential threats out there, that somebody wants to do harm to our citizens that they call the police service." 

There was a noticeable increase in police presence on public transit in the wake of the Wednesday shooting, and additional searches at sports games. 

"The message really is simple — if you see something, say something," said Brad Ross, Toronto Transit Commission spokesman.

There's a similar reaction in Vancouver, where more police officers and security staff are being stationed at some public buildings and events, and on transit.

Legislatures up security but don't close

Across Canada, legislatures continue to be on heightened alert, with some reporting that the days of an open and available parliament may change for good.

“There’s a balance between liberty and security,” said Nova Scotia Kings-Hants MP Scott Brison. “This is a game changer, but how can we approach this and maintain the values of openness and accessibility of democracy?”

No legislatures closed despite additional security measures.  

17 wing security

Security measures have been increased at military bases, such as at CFB Winnipeg 17 Wing, following Wednesday's shootings in Ottawa. (CBC News)

Mubin Shaikhhe, former counterterrorism operative for CSIS and the RCMP, told the CBC that with an elevated threat level, Canadians should expect to see stricter security measures in public places. 

"It's going to have to be a balance between the openness of our society where we're definitely not going to militarize. That's not going to happen. Certainly there should be more visible security. This is the world we're living in," he said.

Veterans, military react

Canada's military will be reviewing security at different military installations across the country, CBC's Vik Adhopia reported earlier in the day from St. John's, N.L. Some bases have already closed their doors to members of the public without an appointment and stationed armoured guards at entrances. 

Soldiers with 17 Wing in Winnipeg, Man., were reeling over Cirillo's death as security has been ramped up at the air force base.

Nathan Cirillo memorial

Residents of Hamilton add to a growing shrine for slain Cpl. Nathan Cirillo, who served with the Argyll and Sutherland Highlanders of Canada regiment. (CBC Radio-Canada)

Two uniformed soldiers carrying assault weapons were standing guard at the entrance to the base as they conducted security checks on Thursday. The chief of reserves and cadets has temporarily ceased cadet and junior Canadian ranger activities nationwide as a precautionary measure. 

Veterans interviewed in Montreal were torn over suggestions that soldiers not wear their uniforms in public, for fear that they could be the target of another attack.

"If he becomes a bullet magnet wearing a uniform, other people are going to get hurt who are not soldiers, so it's a good idea not to wear the uniform," said Roxboro Royal Canadian Legion Service Officer Sidney Wansborough 

Fraser Debney, a retired master corporal, disagreed. He said he refused to cower in the face of the attacks this week.

"I am not going to hide, I’m not going to cover myself up. 

"It’s been a very emotional day. It’s been two brother-in-arms who have been taken down, and as a former soldier, yes I feel it," said Debney.

Condolences pour in for fallen soldier 

Residents of Hamilton added to a growing shrine at a downtown armoury on Thursday for Cirillo, who served with the Argyll and Sutherland Highlanders of Canada regiment. Cirillo's death generated an outpouring of grief across social media

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Members of Canada’s Muslim community offered condolences, and condemned Wednesday's attack and the one earlier this week that resulted in the death of a solder when he was run over by a car in a St-Jean-sur-Richelieu parking lot.

“The Ahmadiyya Muslim Jama’at Canada categorically and unequivocally condemns terror attacks on the Canadian Parliament and the National War Memorial as well as on the Canadian soldiers in St-Jean-sur-Richelieu, Quebec,” the organization said in a statement released Wednesday. “These acts of terror have no basis in any religion.”

In Calgary, a mother whose son died while fighting for militants in Syria says the government must do more about the threat posed by homegrown terrorists in the wake of Wednesday’s attack.

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With files from The Canadian Press