Canada's prime minister said his country will be vigilant, but "not run scared" in the face of two attacks this week in Ottawa and near Montreal, in which two soldiers were killed.
Prime Minister Stephen Harper addressed parliament as it reopened Thursday, a day after a gunman, identified as a convert to Islam, fired dozens of shots inside the building in Ottawa, minutes after he killed a soldier guarding a nearby war memorial.
Harper vowed his country would be undaunted.
"We will not be intimidated. We will be vigilant, but we will not run scared. We will be prudent, but we will not panic," Harper said.
Harper said lawmakers would expedite new powers to counter the threat of radicals.
Lawmakers gave Parliamentary Sergeant-at-Arms Kevin Vickers a prolonged standing ovation Thursday, honoring him for killing the gunman and ending the rampage.
Vickers said in a statement he was touched by the attention, but he credited “the support of a remarkable security team" for making his actions possible.
Related TV report by Al Pessin:
Man arrested near memorial
Underscoring tensions in the capital, Ottawa police arrested a man at gunpoint just steps away from Harper on Thursday.
Harper and his wife were laying a wreath at the National War Memorial to commemorate the killing there of Corporal Nathan Cirillo when police, shouting and with guns drawn, surrounded a man and ordered him to the ground.
Ottawa Police said the man was arrested for “disturbing the crime scene” at the war memorial. It was not immediately clear what was the man's intent.
Employees began returning to the Parliament Hill complex amid tighter security. The House of Commons opened at 10 a.m. (1400 GMT), with the prime minister speaking at that time.
Tighter security was evident all over the sprawling parliamentary zone in downtown Ottawa.
Armed Royal Canadian Mounted Police (RCMP) officers stood outside the door where the gunman, identified as Michael Zehaf-Bibeau, 32, rushed in on Wednesday after shooting Cirillo at point-blank range.
Canadian officials said 32-year-old Michael Zehaf-Bibeau was a Canadian-born citizen who may have also held Libyan citizenship.
They said Zehaf-Bibeau recently applied for a Canadian passport and was hoping to travel to Syria. According to authorities, Zehaf-Bibeau was in Ottawa dealing with a passport issue.
In a statement sent to The Associated Press, Zehaf-Bibeau's parents expressed their sorrow over the incident, but said they had no explanation to offer. They said their son "was lost and did not fit in."
The heart of the capital city of Ottawa had been in lockdown for 10 hours after Wednesday's attack, as police scoured the area for more possible suspects.
Police believe one gunman
Ottawa police Constable Marc Soucy confirmed to The Associated Press Thursday that police are satisfied there was one attacker. Ottawa police Chief Charles Bordeleau told the Canadian Broadcasting Corp. that "there is no longer a threat to public safety."
“There was only one gunman,” said an RCMP officer who was guarding Parliament Hill early on Thursday, checking the identity cards of workers and media going into the parliament complex.
He told Reuters in the confusion Wednesday morning, witnesses saw things from different angles, suggesting the possibility of second shooter, but videos and further interviews showed this was not the case.
Earlier this week, a man whom the prime minister described as a Muslim convert who had been "radicalized" drove a car into two Canadian soldiers in Saint-Jean-sur-Richelieu, about 40 kilometers southeast of Montreal, killing one.
In a brief address to the nation on Wednesday night, Harper pledged to redouble the country's fight against “terrorist organizations.
“Let there be no misunderstanding, we will not be intimidated. Canada will never be intimidated,” he said.
“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.”
Both attacks took place after Canada announced this month it would send six jets to take part in air strikes against Islamic State fighters who have taken over parts of Iraq and Syria.
Harper said Canada would now “redouble our efforts 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.”
Canadian Foreign Minister John Baird, in a telephone conversation with U.S. Secretary of State John Kerry, appeared to link the attack to Canada's participation in the U.S.-led air campaign against the Islamic State group.
Added powers of detention, surveillance
Defense Minister Rob Nicholson said Canada's deployment to Iraq would go on unimpeded.
The two attacks in quick succession could push the Canadian government to pause and rethink before introducing a planned bill to change the Canadian Security Intelligence Service Act, said Wesley Wark, a professor at the University of Ottawa, who is an expert on national security and intelligence issues.
The bill to boost the powers of Canada's main spy agency, CSIS, was due to be introduced in parliament this week.
While speaking to parliament, Harper said the government will expedite plans to give more powers of detention and surveillance to security agencies in the wake of an attack on Parliament.
“They need to be much strengthened, and I assure you, Mr. Speaker, that work which is already under way will be expedited,” he told the House of Commons Thursday morning.
President Barack Obama spoke by phone with Prime Minister Harper after Wednesday's attacks and said it was important for U.S. and Canadian counterterrorism authorities to continue working in sync.
The United States has boosted security at its embassy in Canada. The State Department said all embassy employees have been accounted for.
"We are currently restricting the movement of embassy personnel, as a cautionary measure," said Marie Harf, State Department deputy spokesperson.
Some material for this report came from Reuters and AP.