A woman cries as she attends a makeshift memorial for Cpl. Nathan Cirillo outside of The Lieutenant-Colonel John Weir Foote Armoury in Hamilton, October 23, 2014. [Photo/Agencies]

MOTHER'S APOLOGY

A woman who identified herself as the suspect's mother issued a statement earlier on Thursday apologizing for her son's apparent actions.

"No words can express the sadness we are feeling at this time," said the woman, Susan Bibeau, in a statement provided to the Associated Press. "We send our deepest condolences."

Zehaf-Bibeau stayed at a homeless shelter in a downtrodden part of Ottawa for at least a week before the attack, multiple people at the site said on Thursday.

A friend, Steve Sikich, who had lived with Zehaf-Bibeau at a Vancouver homeless shelter said Zehaf-Bibeau had rambled about wanting to travel to Libya and join the Islamic State. "He didn't seem like a bad guy," Sikich said.

Police have interviewed some of the people who were at the Ottawa shelter but none of the people with whom they spoke said they had any knowledge of his plans.

Tighter security was evident all over the sprawling parliamentary zone in downtown Ottawa.

The flag flying over Parliament's Centre Block, where the gunman had burst in on Wednesday morning, was at half mast and bullet holes could be seen in the carpet just inside the front door and in the masonry in the hallway.

As police hunted for Zehaf-Bibeau in the parliament building, Harper spent a few terrifying moments hiding in a closet-like space in the building, listening to a barrage of gunshots that one member of parliament thought was machine gun fire, the Winnipeg Free Press reported.

"Because we heard so many gunshots, the impression I had was there were several gunman outside with machine guns about to enter and spray the caucus," the paper quoted Jay Aspin, a member of parliament who was present, as saying. "It was pretty traumatic."