A gunman shot and killed a soldier at the National War Memorial in Ottawa, before running into the parliament building where he was shot in an exchange of gunfire with police.
Cpl. Nathan Cirillo was shot while guarding the memorial in central Ottawa at 09:52 (14:42 BST), and witnesses reported seeing the gunman run towards the parliament building.
Ministers and staff in the building barricaded themselves into rooms and the public were warned to keep away from Parliament Hill as police hunted for the suspect. The authorities caught him a few metres from a door to the NDP caucus room and exchanged fire, killing the gunman. Sergeant-at-arms Kevin Vickers, 58, has been widely credited with shooting the armed suspect dead.
The Globe and Mail released a video of police shooting and killing the suspect inside the parliament buildings.
The gunman has been named by Canadian media as Zehaf-Bibeau, a 32-year-old Canadian citizen.
Despite members of the public performing CPR at the scene and being rushed to hospital to receive treatment, Cpl. Cirillo died of his injuries.
Ottawa Hospital says that they received three other patients from the shootings, who were all treated for minor, non-life threatening injuries.
Prime Minister Stephen Harper was addressing the cabinet at the time of the attack, but he was safely evacuated and later condemned the incident as a “despicable attack”.
Earlier reports of further gunshots at the Rideau Centre shopping mall and Chateau Laurier hotel appears to have been false, say police. However, parts of downtown remain on lockdown as police investigate the possibility of more gunmen being involved.
The incident came hours after Canada raised its terror threat level to medium in response to “general chatter” online from radical Islamist groups.
On Tuesday, Martin Couture-Rouleau, a radicalised Muslim, was killed by Quebec police after killing one soldier and injuring another after striking them with his car.
The Royal Canadian Mounted Police (RCMP) have asked for anyone with photographs relating to the shootings to share them with police at http://rcmp.ca/-hSn.