The 29-year old Canadian also had a criminal record in Quebec and British Columbia. The Islamic State (IS, which was formerly known as Islamic State of Iraq and al-Sham) terrorist group claims that he was one of their sympathisers and posted his alleged photo on social media.
Zehaf-Bibeau killed an unarmed Canadian military guard in Ottawa on Wednesday and then entered the parliament building, presumably to massacre lawmakers. He was shot by the sergeant of arms.
The attack came two days after another Muslim convert, Martin Couture-Rouleau, ran over two Canadian soldiers in Saint-Jean-sur-Richelieu, Quebec. Warrant Officer Patrice Vincent was killed in the incident.
Police killed Richelieu after a car chase.
Authorities had raised terror threat level in Canada to medium after the first attack and hiked it to high after the Ottawa shootings.
Weeks before the two attacks, the Islamic State had urged its sympathisers to target government offices in the United States and Canada in retaliation for air strikes on their hideouts in Iraq and Syria.
On Thursday, Canadian Prime Minister Stephen Harper told his nation that the government had reasons to believe the attacks were inspired by the Islamic State group.
“We will be vigilant, but we will not run scared. We will be prudent, but not panic,” said Mr Harper while addressing the parliament. “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.”
US President Barack Obama, however, said it was still not clear if “this was part of a broader network or plan or whether this was an individual or series of individuals who decided to take these actions”.
But US intelligence officials, who spoke to various media outlets, said they saw a pattern in these attacks, pointing out that other similar incidents across the world were traced to the Islamic State group as well.
They noted that on Sept 25 a Muslim convert, Alton Nolen, allegedly beheaded a co-worker in Oklahoma.
Police said he was an ISIL sympathiser.