A gunman attacked Canada's parliament on Wednesday, with shots fired near where Prime Minister Stephen Harper was speaking, and a soldier was killed at a nearby war memorial, stunning the Canadian capital.
The gunman in the parliament building was shot dead, and Harper was safely removed. The killing of the Canadian soldier was the second this week with a possible link to Islamic militants.
Witness accounts indicated the man who shot dead the soldier guarding the National War Memorial in central Ottawa, went on to attack the parliament building minutes later. Canadian police said, however, they could not confirm it was the same person.
The shooting followed an attack on two soldiers in Quebec on Monday carried out by a convert to Islam. U.S. officials said they had been advised the dead gunman in Wednesday's shootings was also a Canadian convert to Islam.
Canadian police were investigating a man named Michael Zehaf-Bibeau as a possible suspect in Wednesday's attack, said a source familiar with the matter. U.S. government sources said he was born Michael Joseph Hall but later changed his name.
Harper was defiant when he spoke on television 10 hours later, with some buildings still under emergency lockdown and police saying they were still looking into the possibility of a second gunman.
Harper said it would become clear in days to come whether the man who launched a gun attack on parliament - and whom he called "a terrorist" - was acting alone or had accomplices. "Let there be no misunderstanding. We will not be intimidated. Canada will never be intimidated," he said.
"In fact this will lead us to strengthen our resolve and redouble our efforts - and those of our national security agencies - to take all necessary steps to identify and counter threats and keep Canada safe here at home."
Canada announced this month it was joining the battle against Islamic State fighters who have taken over parts of Iraq and Syria, and Harper said the attack would prompt Canada to redouble its efforts to fight against "terrorist organizations" abroad.
After Harper spoke, police lifted their blockade of the downtown area except on Parliament Hill.
The attacks in Ottawa and Quebec took place as the Canadian government prepared to boost the powers of its spy agency, the Canadian Security Intelligence Service. Public Safety Minister Stephen Blaney said last week the new legislation would let the agency track and investigate potential terrorists when they travel abroad and ultimately prosecute them.
Attack near Harper
The incident, shocking in Canada's normally tranquil capital, began shortly before 10 a.m. ET (1400 GMT). A construction worker who was on the scene told Reuters he heard a gunshot, and then saw a man with a scarf over his face running towards parliament.
"He was wearing blue pants and a black jacket and he had a double barrelled shotgun and he ran up the side of this building here and hijacked a car at gunpoint," construction worker Scott Walsh told Reuters.
He said the driver got out safely, then the man drove the car to the Centre Block, the main building on Parliament Hill, a sprawling complex of buildings and open space in downtown Ottawa.
The assault in parliament took place very near the room where Harper was meeting with members of his Conservative party, a government minister said. Witnesses said a flurry of shots were fired after a gunman entered the parliament building, pursued by police.
"PM (Harper) was addressing caucus, then a huge boom, followed by rat-a-tat shots. We all scattered. It was clearly right outside our caucus door," Treasury Board Minister Tony Clement told Reuters.
Security in Ottawa came under criticism after the gunman was able to run through the unlocked front door of the main parliament building.
"It caught us by surprise ... If we had known that this was coming, we would have been able to disrupt it," Gilles Michaud, assistant commissioner of the Royal Canadian Mounted Police, (RCMP) told a news conference.
It was unclear whether there was any connection between Wednesday's shootings and an attack on Monday when a convert to Islam ran down two Canadian soldiers with his car, killing one, near Montreal, before being shot dead by police in the first fatal attack on Canadian soil tied to Islamic militants.
No group, Islamic or otherwise, claimed responsibility for either the attack in Ottawa or the one near Montreal. Monday's attacker, 25-year-old Martin Rouleau, who converted to Islam last year, was among 90 people being tracked by the RCMP on suspicion of taking part in militant activities abroad or planning to do so.
Guns drawn in Parliament
From witness accounts it appeared the suspect dashed into parliament, ran past the room where Harper was speaking and was gunned down outside the entrance to the library, only about 60 feet (20 meters) away.
Dramatic video footage posted by the Globe and Mail newspaper showed police with guns drawn inside the main parliament building. At least a dozen loud bangs can be heard on the clip, echoing through the hallway.
Conservative Member of Parliament Peter Goldring said Sergeant-at-Arms Kevin Vickers shot dead the gunman who had been running past the caucus room where Harper was.
He came out of his office with a weapon and fired and apparently dropped him," Goldring said. "He even went back into his office again and reloaded to come out again to give protection, because the sense was that nobody was sure whether it was one person or whether it was multiple people who were involved."
Three people injured in the attacks were treated at hospital and released.
Canada said on Tuesday it had raised the national terrorism threat level to medium from low because of a rise in "general chatter" from radical groups such as Islamic State and al Qaeda but said there had not been a specific threat.
The RCMP's Michaud said the threat level on Parliament Hill had been on medium for some time.
The soldier who died in the shooting at the War Memorial was identified as Cpl. Nathan Cirillo, according to his aunt. It was not clear if Cirillo was armed or not when he was shot.
'You are in danger here'
The attack on the heart of the country's government shook Canada's self-image as generally non-violent, particularly compared to the United States, where gun violence is much more common. Canadian cities and towns hiked security around government buildings, schools and mass transit systems.
When the shooting started, most members of parliament were in the two caucus rooms past which the gunman ran. Members were told to lock or barricade themselves in their rooms or offices, and stay away from the windows.
Pictures sent from both caucus rooms where the parties were meeting showed piles of chairs jammed up against the doors to prevent anyone from entering. Late in the day, many members were allowed to leave.
U.S. officials said there was no specific indication of a similar attack in the United States, a strong Canadian ally, but reinforced warnings to Americans to be alert.
Compared with Capitol Hill in Washington, security on Parliament Hill is fairly low key. Anybody could walk right up to the front door of parliament's Centre Block with arms and explosives without being challenged before entering the front door, where a few guards check accreditation.
Canadian and U.S. stock markets declined after the shootings in Ottawa. The Toronto Stock Exchange's TSX index dropped 1.6 percent, while the S&P 500 gave back 0.7 percent.
Mass shootings are relatively rare in Canada, which has stricter gun laws than the United States, and the regulations at one point included a national registry of rifles and shotguns. Legislation was passed in 2012 to scrap the registry.