The gunman who killed a Canadian soldier before being shot to death in Parliament visited his mother for the first time in five years just a week before he opened fire, the mother said in a statement today.

Michael Zehaf-Bibeau, 32, has been identified as the shooter behind Wednesday's attack in Ottawa, an act that has appalled his own mother.

"I am mad at our son, I don't understand and part of me wants to hate him at this time," wrote Susan Bibeau in a statement on behalf of herself and her husband, Bulgasem Zehaf. Bideau, who has been the director general of Canada's Immigration Division since April 2009, gave the statement to the Associated Press.

Bideau said she had no insight into her son's actions.

"I, his mother, spoke with him last week over lunch, I had not seen him for over five years before that. So I have very little insight to offer," she wrote.

Her statement was in response to an AP question asking if she knew about any problems her son was having before the shooting.

"You write that our son was vulnerable, we don't know, we (he) was lost and did not fit in," she wrote.

The gunman, whose full name is listed as Michael Joseph Paul Zehaf Bibeau in Vancouver court documents, had been arrested in the past.

In 2004, he was arrested on drug-related charges when he lived in Montreal, according to court documents. He was later charged with robbery in 2011 in Vancouver, though the outcome of both cases were not immediately clear, the documents indicate.

Bibeau apologized "apologize for all the pain, fright and chaos he created. We have no explanation to offer."

"No words can express the sadness we are feeling at this time," the statement read. "We are so sad that a man lost his life. He has lost everything and he leaves behind a family that must feel nothing but pain and sorrow. We send our deepest condolences to them although words seem pretty useless. We are both crying for them."