The Harper government's nerve centre for emergencies issued a Canada-wide alert more than five hours after traumatic shootings at the National War Memorial and Parliament Hill, warning that up to five other assailants were involved in the attack.

The erroneous Oct. 22 report from the Government Operations Centre to top officials claimed to be drawing on news media and other open sources for this and other sometimes dubious information ­— raising questions about the ability of senior intelligence personnel to disseminate reliable data to front-line security.

"As of 13:04 EDT, open sources reported that possibly five assailants may have been involved in this event," says an internal situation report sent to emergency personnel in federal departments and in the provinces and territories.

"Open sources reported that after an intense search, security services shot and killed at least one assailant."

The document, distributed electronically sometime after 3 p.m. on Oct. 22, is among six formal communications issued by the secretive Government Operations Centre and obtained by CBC News under the Access to Information Act. Small sections of the documents were censored under security exemptions.

A situation report issued sometime after 8 p.m. that day repeated the erroneous information about there being as many as five assailants — again citing open sources — and noted that "RCMP has advised all personnel in downtown buildings to stay clear of windows and roofs," presumably because of the threat of snipers.

Alarmist tone

Minutes later, Ottawa city police notified the public that a "threat to public safety in the area no longer existed" — far different from the alarmist tone that had just been issued widely by the federal emergency office.

The situation reports, distributed to officials at the Treasury Board, Privy Council Office and other major departments, prompted a general lockdown of federal buildings in the downtown core until mid-evening. Public servants were told to hide under desks, stay away from windows and move to inner, windowless offices.

It's not clear where media reports of as many as five gunmen originated. Most media outlets, including CBC News, reported RCMP and other security personnel were on the alert for a possible second or even third accomplice.

The six situation reports all appear to rely heavily on occasionally contradictory news media items, rather than on hard information from front-line officers dispatched to the search for accomplices.

The Government Operations Centre is a 24-hour, seven-day-a-week facility in an undisclosed location that "provides strategic-level co-ordination … in response to an emerging or occurring event affecting the national interest," according to the website of Public Safety, the department in charge.

Accurate, timely and comprehensive information. — Public Safety website description of Government Operations Centre reports

"The GOC conducts risk assessments based on information and intelligence to provide senior and elected officials and the private sector with accurate, timely and comprehensive information to quickly develop proper responses to an occurring event."

Intelligence expert Wesley Wark raised questions about the role of the Government Operations Centre that day, noting the RCMP and Ottawa city police were the lead agencies, and the centre "was peripheral on the day as a source of information."

"This suggests that emergency management procedures for the NCR [National Capital Region might need to be reviewed," said Wark, an academic at the University of Ottawa, on examining copies of the situation reports.

He added that the 3 p.m. message about multiple assailants "looks like the product of fatigue. No reason for it to have conveyed an alarming message about a possible five assailants."

The centre came under fire in September this year after the Toronto Star obtained documents showing it has kept close tabs on some 800 public demonstrations and protests since 2006, drawing on Canadian Security Intelligence Service and RCMP information.

The public release of the doubtful situation reports about the Oct. 22 shootings follows another CBC News investigation that found the Privy Council Office issued a security alert five days before the shooting warning of a potential "violent act of terrorism in Canada."

It's unclear whether the Privy Council alert prompted stepped-up vigilance, but some security experts have questioned how the lone Oct. 22 shooter, Michael Zehaf-Bibeau, still managed to enter Centre Block and fire his hunting rifle repeatedly just metres from the prime minister, cabinet ministers and dozens of MPs.

'Unclassified products'

The Government Operations Centre, which also handles natural disasters such as extreme weather events, is distinct from the RCMP's National Operations Centre, another round-the-clock facility that deals with suspected criminal activities, and — unlike its parallel facility at Public Safety — encourages public contact through a telephone line or email. The RCMP centre had access to closed-circuit video footage in the parliamentary precinct throughout the Oct. 22 events.

The Government Operations Centre, run by director general Craig Oldham, issued its first mass email about the shooting incident at 10:12 a.m., a terse report citing open sources about the wounding of an honour guard at the National War Memorial, and shots fired in the Centre Block, with no reports of injuries.

"Further products related to this event will not be issued unless there are significant changes to the situation," the email advised. A French-language version of the same email was not issued until more than an hour later.

A spokesperson for Public Safety said the centre was in early contact with security services "to ensure the GOC was able to co-ordinate collective government response and share information as accurate as possible, during difficult and uncertain circumstances."

But Josée Sirois added that the situation reports "were unclassified products and therefore would not include any classified material from security partners."

The communications were sent to federal departments, operations centres of provincial and territorial governments, key private-sector critical infrastructure owners or operators, and other emergency management officials, she said in an email.

Sirois did not respond to a direct question about the source of the erroneous information about as many as five assailants.

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