In a tear-filled interview, Susan Bibeau said she did not know what to say to those hurt in the attack.
“Can you ever explain something like this?” she said. “We are sorry.”
Michael Zehaf-Bibeau, 32, an Islamic convert, shot and killed a Canadian soldier at a Second World War monument outside the country’s parliament building on Wednesday.
Zehaf-Bibeau, born Michael Joseph Hall, had a criminal record for drug use and was barred from leaving Canada after being designated by authorities as a “high risk traveller”, meaning authorities believed he could travel overseas to join arms with terrorists.
Court records that appear to be the gunman’s show that he had a long criminal record with a string of convictions for assault, robbery, drug and weapons offences, and other crimes.
David Bathurst, a friend of Zehaf-Bebeau, said the attacker was asked recently to leave the mosque. “I think he must have been mentally ill,” Mr Bathurst told the Canadian Globe and Mail newspaper, adding that he would talk extensively about the devil.
“We were having a conversation in a kitchen, and I don’t know how he worded it: He said the devil is after him,” he said. “He seemed unstable.”
Investigators offered little information about the gunman in Ottawa.
Canadian police conceded that Zehaf-Bibeau was the lone gunman, the second attack in three days in what the prime minister described as terrorism.
The heart of the capital city of Ottawa had been in lockdown after Wednesday’s attack, with fears that other gunmen might be on the loose. Ottawa police constable Marc Soucy confirmed 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”.
The two attacks stunned Canadians and raised concerns their country was being targeted for reprisals for joining the US-led air campaign against the extremist Islamic State group in Iraq and Syria.
Yesterday, prime minister Stephen Harper visited the National War Memorial where the soldier was killed to lay a wreath.
Earlier, Harper called the shooting the country’s second terrorist attack in three days.
A man Harper described as an “ISIL-inspired terrorist” on Monday ran over two soldiers in a parking lot in Quebec, killing one and injuring another before being shot to death by police. Like the suspect from Wednesday’s shooting in Ottawa, he was a recent convert to Islam.
Witnesses said the soldier posted at the National War Memorial, identified as Cpl Nathan Cirillo, was gunned down at point-blank range by a man carrying a rifle and dressed all in black, his face half-covered with a scarf. The gunman appeared to raise his arms in triumph, then entered Parliament, a few hundred yards away, where dozens of shots soon rang out, according to witnesses.
People fled the complex by scrambling down scaffolding erected for renovations, while others took cover inside as police with rifles and body armor took up positions outside and cordoned off the normally bustling streets around Parliament.
On Twitter, Canada’s justice minister and other government officials credited 58-year-old sergeant-at-arms Kevin Vickers with shooting the attacker just outside the MPs’ caucus rooms. Vickers serves a largely ceremonial role at the House of Commons.