Donna Leinwand Leger and Doug Stanglin

USA TODAY

OTTAWA — Prime Minister Stephen Harper, speaking to Parliament Thursday one day after a gunman rampaged through the ornate building, said Canadians "will not run scared" and proposed tightening police and surveillance procedures to go after terrorists.

In a dramatic opening of the session, Kevin Vickers, the sergeant-at-arms who traditionally leads the MPs into the chamber, received a sustained and emotional round of applause for his quick action on Wednesday in fatally shooting the gunman.

Vickers, a 58-year-old retired officer in the Royal Canadian Mounted Police, appeared on the verge of tears as waves of applause swept through the room.

Harper, in his address to members, underscored the government's resolve in response to the Wednesday shooting that left a guard at the National War Memorial dead, and a separate incident Monday in Quebec that killed one soldier and injured a second.

"We will be vigilant, but we will not run scared. We will be prudent, but not panic," Harper told members of Parliament to repeated applause. "As for the business of government, we are here in our seats, in our chamber, in the very heart of our democracy, and we are working."

The prime minister, vowing that Canada "will never yield to terrorism," said the government would expedite the passage of new laws to strengthen the police in the areas of detention and surveillance.

"We live in dangerous times, yes, but the mission of our country and the work of this Parliament goes on, and so does the work throughout this city," Harper said.

The gunman, who was fatally shot during the assault on Wednesday, has been identified as Michael Zehaf-Bibeau, a Canadian born in 1982 who was a recent convert to Islam.

Canadian police confirmed Thursday that only one gunman was involved in the shootings in and around the Parliament building that left Cpl. Nathan Cirillo dead. The motive for the shootings remained unclear.

The suspect's mother, Susan Bibeau, said in an e-mail Thursday to the Associated Press that she had "very little insight to offer" about him because she had not seen him for over five years before they spoke last week over lunch

"I am mad at my son," the email said, explaining that he seemed lost "and did not fit in."

In a brief conversation with the AP later Thursday, Bibeau said she was devastated for the victims of the attack. "If I'm crying it's for the people," she said, struggling to hold back tears. "Not for my son."

She added: "Can you ever explain something like this? We are sorry."

The Globe and Mail newspaper of Toronto reported that Zehaf-Bibeau was recently designated a "high-risk traveler" by the Canadian government and that his passport had been seized.

It said Zehaf-Bibeau had a criminal record for drug possession, credit card forgery and robbery.

The shaken capital slowly tried to return to normal on Thursday, with members of Parliament returning to work, although the Parliament buildings were otherwise closed to visitors.

The National War Memorial remained cordoned off with police tape on Thursday, but MPs and government officials stopped by to pay their respects.

Harper arrived by motorcade around 9 a.m., joining by Liberal Leader Justice Trudeau and various Conservative Cabinet ministers.

In a personal touch in his remarks Thursday, Harper urged MPs — many of whom had barricaded doors inside the building during the shooting — to seek medical help if they are suffering stress from Wednesday's attack.

Harper said earlier that the first incident, on Monday, in which two soldiers were run down, was carried out by an "ISIL-inspired terrorist," referring to the Islamic State extremist group in the Middle East. That assailant, also a recent convert to Islam, was shot to death by police.

In Washington, President Obama condemned the shootings as "outrageous" and said: "We have to remain vigilant." The U.S. Embassy in Ottawa was locked down as a precaution, and security was tightened at the Tomb of the Unknown Soldier at Arlington National Cemetery, just outside Washington.

Contributing: Associated Press