Ottawa was rocked by violence Wednesday after a gunman fatally shot a soldier guarding the National War Memorial. The gunman then opened fire in the Parliament building, unleashing terror in the Canadian capital before he was shot and killed by a sergeant-at-arms.
The gunman, identified as 32-year-old Michael Joseph Hall, was a convert to Islam and had been using the name Michael Zehaf-Bibeau, sources told NBC News. The victim, identified by his aunt as Cpl. Nathan Cirillo, died hours later.
"Corporal Cirillo was killed today, murdered in cold blood," Prime Minister Stephen Harper said in address to the nation Wednesday night. "But let there be no misunderstanding, we will not be intimidated, Canada will never be intimidated."
Authorities told NBC News that Hall had a history of low-level criminal offenses but has no known connection to ongoing terrorism investigations.
The attack began shortly before 10 a.m., according to Ottawa Police Service Chief Charles Bordeleau, when local law enforcement officials received multiple emergency calls reporting a shooting near the National War Memorial. "I thought it was just firecrackers going off," a witness told NBC News. "So I looked across the street, and there was a man with a rifle shooting at a bunch of people."
The gunman then hijacked a car, according to NBC News, and drove about a third of a mile to the Parliament building, where lawmakers were in session.
Some members of Parliament, responding to the sounds of shots fired, barricaded meeting room doors with furniture as police and security forces put the entire complex on lockdown. Prime Minister Stephen Harper, who was also on Parliament Hill at the time, was moved to safety. Several people were injured before the gunman was shot and killed in Parliament's central Hall of Honor by the sergeant-at-arms, 58-year-old Kevin Vickers.
A hospital spokesperson said four patients had arrived at the Ottawa Hospital's Civic Campus; three had minor, non-life threatening injuries and were later released.
"Our city, Ottawa, the capitol of our country has seen and lived through tragedy in our past and doing so again today," said Ottawa Mayor Jim Watson. "A different sort of tragedy, whose origins are not yet fully known, causes not yet fully understood."
A day later, after an extensive sweep of the surrounding area, police officials told the Canadian Broadcasting Corporation on Thursday that they believed the attack to be the work of a lone gunman.
"This is a dynamic and unfolding situation," Gilles Michaud, a commander with the Royal Canadian Mounted Police, said Wednesday.
Later Wednesday night, Ottawa police announced they had lifted the safety perimeter in Downtown Ottawa after an ongoing investigation found no threat to public safety in the area. "Residents will continue to see an increased police presence in key areas in the coming days," police said in a statement.
The shooting came just two days after Martin Rouleau, a recent convert to Islam who is suspected to have been influenced by the Islamic State of Iraq and Syria, drove over two Canadian soldiers, killing one. The following day, Canada raised its domestic terrorism threat level, citing increased chatter by extremist Islamist groups.
In an address to the nation Wednesday night, Prime Minister Harper vowed to "strengthen our resolve and redouble our efforts" to identify and counter terror threats against Canada, as well as to "work with our allies around the world and fight against the terrorist organizations who brutalize those in other countries with the hope of bringing their savagery to our shores."
Earlier this month, members of Canada's Parliament agreed to join the U.S.-led coalition to fight the terrorist group in Iraq. ISIS has responded to the growing coalition by calling on sympathizers worldwide carry out so-called "lone wolf" attacks against civilian and military targets in countries assisting the U.S. campaign in Iraq and Syria.
"This is exactly, again, what intelligence officials have been worried about," Michael Leiter, former director of the U.S. National Counterterrorism Center, told NBC News.
The Muslim reformist group Ahmadiyya Muslim Jama'at released a statement Wednesday night condemning the attack. "These acts of terror have no basis in any religion," the group said. "As Canadians, we pray that God Almighty protect all Canadians from harm and that these terrorists are brought to justice."
President Obama spoke by phone with Prime Minister Stephen Harper to express solidarity, the White House said Wednesday. Obama condemned the attacks, reaffirmed the two countries close relationship and agreed to coordinate their response.
Although there is "no specific reporting indicating a threat to the United States," according to the FBI, the agency said that its field offices and government partners would "remain vigilant" and "stand ready to assist our Canadian partners."