A soldier at the National War Memorial in Ottawa was killed by a gunman who then moved up the street to launch an attack on Parliament's Centre Block, where two people were wounded. The assailant was shot dead by the sergeant-at-arms of the House of Commons.
The National Assembly in Quebec City, the site of a 1984 attack by a gunman that left three dead, was quickly closed to the public, while movement was limited in and around government buildings.
Premier Philippe Couillard urged caution in establishing links between the Ottawa shooting and Monday's incident in Saint-Jean-sur-Richelieu, Que., where a man with jihadist sympathies struck two soldiers with his car, killing one of them.
The New Brunswick legislature in Fredericton closed for the day, while the Nova Scotia legislature in Halifax and the British Columbia legislature in Victoria tightened security to allow in only people with security passes.
Craig James, the clerk of the B.C. legislature, said security personnel were stationed at every entrance to the building, but the legislature was not in a full lockdown.
Ontario's political leaders considered suspending question period Wednesday but decided that would send the wrong signal after the director of security services said there was "no known threat" to the legislature in downtown Toronto.
"Our belief is that people who are using violence to undermine democracy want us to be silenced, and we refuse to be silenced," Premier Kathleen Wynne told the legislature, earning a standing ovation and praise from the opposition parties.
Ontario Community Safety Minister Yasir Naqvi said the province was briefed last week about a possible raising of the national internal threat level, but there was no warning of an imminent threat.
In B.C., some provincial politicians were warned this week about "a heightened concern from entities in Ottawa," said James, adding there was nothing to indicate the province's legislature was at risk.
The federal government confirmed Tuesday it had raised its threat level due to an increase in "general chatter from radical Islamist organizations."
In Saskatchewan, security was beefed up for Wednesday's throne speech kicking off the fall session of the legislature, with Premier Brad Wall announcing only those with invitations would be allowed in while the general public would be barred.
The ceremony before the speech was also moved inside the legislature in Regina due to concern for military personnel and international diplomats who attended the event. Police officers swept the building beforehand for any threats.
Security was also heightened at the Manitoba legislature, where police cruisers were stationed outside.
Alberta Premier Jim Prentice said the government was monitoring the events in Ottawa but would not talk about security issues at the legislature.
"We have robust security that includes armed Sheriffs, security instruments and protocols with the Edmonton Police service," Prentice said in a statement. "No further details will be disclosed for security reasons."
The Newfoundland and Labrador House of Assembly in St. Johns was not sitting Wednesday.
Some members of Ontario's parliament said it was time to consider arming security staff at the legislature, but the government said it would leave those decisions to the security experts.
"I'm surprised it gets rejected every time it comes up," said interim Progressive Conservative Leader Jim Wilson. "Out of hand it gets rejected."
Wilson said he's been raising the issue of arming security staff at Queen's Park since the deadly 1984 shooting at the National Assembly, but government officials said only that there are constant reviews of security at the Ontario legislature.
"We are always looking at enhancing our security when we can, where we can," said sergeant-at-arms Dennis Clark, the only one who's armed in the legislature. "I have a sword."
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