CANADA has vowed to toughen laws against terrorism as an ­opinion poll showed a majority of Canadians lack confidence in the ability of their security services to deter homegrown radicals, who struck twice in the past week.

Investigators said there was no apparent link between the two attackers, who killed a soldier each in Quebec and the capital Ottawa, but Canadians are worried about the parallels.

Police said the assailants, who were both shot dead, had been radicalised.

Justice Minister Peter MacKay said the government would act swiftly and go beyond the terms of a bill already planned that would strengthen the powers of the Canadian Security Intelligence Service spy agency.

He said: "We're looking to see if there is a way in fact to improve or build on those elements of the criminal code that allow for pre-emptive action, specifically in the area of terrorism.

"This has been an incredible motivational experience to say the least, in light of what took place this week."

Canadians mourning the two soldiers adjusted to a tighter ­security cordon in Ottawa, where Wednesday's attacker was shot dead inside the parliament building near where Prime Minister Stephen Harper was meeting with lawmakers.

In Istanbul, packets of an unidentified yellow powder were sent to the Canadian, US, Belgian and German consulates, prompting security alerts. One Canadian consulate employee came directly into contact with a suspicious package and six others had indirect exposure.

Meanwhile, an opinion poll by the Angus Reid Institute found 55 per cent of Canadians were not confident in the police's ability to thwart attacks by homegrown radicals.

Some 66 per cent of the 1,491 people polled this week said they would prefer authorities to focus on securing the nation's borders and dealing with homegrown threats, rather than prioritising foreign military intervention or foreign aid.

Canadians flocked to the national war memorial in Ottawa where Corporal Nathan Cirillo, 24, was shot dead at the start of a daylight attack by a man police identified as Michael Zehaf-Bibeau, a 32-year-old Canadian citizen.

Police believe that Zehaf-Bibeau acted alone and independently of 25-year-old Martin Rouleau, who on Monday drove over two soldiers in Quebec, killing 53-year-old warrant officer Patrice Vincent.

After the attacks, Mr Harper said Canada would not be deterred from taking part in airstrikes against Islamic State (IS) militants in the Middle East. Two long-range patrol aircraft were due to depart Nova Scotia yesterday.

Police said Zehaf-Bibeau had travelled to Ottawa seeking a ­passport and intended to travel to Syria, a hot spot of IS activity. Zehaf-Bibeau, who was born in Montreal, had lived in Calgary for a period.

The authorities in Ottawa ­yesterday lowered many of the metal barriers that had blocked public access to the area around the war memorial, moving the ­capital closer to normalcy. But officers continued to surround the Parliament buildings into which Zehaf-Bibeau ran after shooting the soldier.

"I feel tremendous sadness," said April Hall, 43, a doctor from London, Ontario, as she sat near the monument wiping tears from her eyes. "This is a memorial to those who sacrificed their lives for Canada, and there was a sacrifice right here on the spot."

Bouquets of flowers were stuck into the gate's scrollwork, as workers and visitors adapted to the tighter security restrictions in a city normally proud of its openness.

Mr Cirillo's body was moved from Ottawa to his hometown of Hamilton, Ontario, along a 310-mile stretch of highway called the "Highway of Heroes" in honour of soldiers.

The Islamic Supreme Council of Canada and Muslims Against Terrorism also planned to hold a memorial for the two slain soldiers.