Acquaintances of the Ottawa gunman who killed a soldier and shot up Parliament claim that he was a crack cocaine and heroin addict who tried in vain for years to get clean.

Michael Zehaf-Bibeau, 32, shot and killed Cpl. Nathan Cirillo, then attempted to shoot up Parliament before he was killed himself. He reportedly entered a detox in 2012 to kick his drug habit, while those who met him at homeless shelters throughout Canada said he relied on constant prayer as a means of trying to get over his addiction. He carried the Koran around with him as a means of trying to “heal” himself from addiction, but became withdrawn when he was abusing drugs.

“He was isolating himself. He was always sleeping. For three days he wasn’t talking,” said Abdel Kareem Abubakir, a volunteer at the Ottawa shelter that Zehaf-Bibeau stayed in earlier this month. “His intention was to get a passport and get home. He had to stay away from drugs.”

It also appears that Zehaf-Bibeau had a history of being in trouble with the law as a result of his addiction. He pleaded guilty and was sentenced to 60 days in prison in Quebec for drug possession in 2004, in addition to being sentenced to a day in jail in Vancouver for robbery and uttering threats in 2011.

Prior to his Vancouver trial, he asked to go to jail as a means of trying to overcome his crack addiction and “as a sacrifice to pay for his mistakes in the past.” However, psychiatrists did not identify any type of mental disorder in Zehaf-Bibeau.

Susan Bibeau issued a statement last Thursday on behalf of her and her husband, Bulgasem Zehaf, stating they had “no explanation to offer” for the shooting. “I am mad at our son, I don’t understand and part of me wants to hate him at this time,” she said in an e-mail to the Associated Press. “I have very little insight to offer. No words can express the sadness we are feeling at this time. 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.”