The police report was undertaken after Cpl. Nathan Cirillo was gunned down at the National War Memorial and shooter Michael Zehaf-Bibeau stormed Parliament Hill's Centre Block.
CBC News learned the report revealed the large scale police response caused mass confusion around downtown Ottawa.
The report also indicated most office buildings in Ottawa are prepared for a fire or bomb threat, but not for active gunmen.
"Not everyone has a policy or procedure in the event of an active shooter in the building, or a threat in environment around your building," said Insp. Mark Ford, a member of the Ottawa police emergency operations directorate.
Ford said police learned about this gap when officers enacted a large safety zone on Oct. 22.
The perimeter stretched several blocks around the war monument and Parliament Hill, which pushed pedestrians away and kept people inside buildings that were within the perimeter.
Kids well-trained, parents aren't, police say
Officers discovered many people stood near windows watching the action outside, which could have been within the line of fire. Others had darted from their buildings before an official police lockdown was put in place.
"Our kids are well-trained, well-educated and well-rehearsed, but the parents in the community have a lot to learn," Ford said.
Ottawa City Hall has heeded the advice from police, though, by reviewing its security policies and reaching out to federal departments such as the Treasury Board, says Pierre Poirier, the Chief of Security & Emergency Management at the City of Ottawa.
Working with Ottawa police, Poirier said the city now has an "Active Attacker" policy, which closely mirrors how schools deal with nearby dangers.
"They use the idea of lockdown, secure and safe facility and safe zone," Poirier said.
"We align the language so parents know how their kids are taken care of, and so parents know what to expect in terms of procedures here at city hall and Constellation Place."
Poirier said staff members are currently being educated on the proper procedure for different threat levels. That includes when doors should be locked, when and where people should hide and who is in charge of giving those orders.
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