Turkish authorities have begun an investigation, the CBC's Jeff Semple reported Friday morning.
"The Canadian, Belgian and German consulates in Istanbul have all been evacuated after all three received a suspicious package this morning, according to reports in the Turkish media," Semple said in London.
"The letter containing a yellow substance was examined in line with regular procedures," Turkey's disaster management agency, AFAD, said in a statement.
One consulate employee came directly into contact with the suspicious package, and six others had indirect exposure, the Turkish statement said.
Everyone working at the Istanbul consulate is safe and accounted for, the Department of Foreign Affairs and International Trade said in a statement.
A consulate employee speaking to a Turkish television interviewer said workers received an email telling them to leave the consulate immediately.
"We couldn't grab our bags or jackets they took us outside we gathered outside the consulate," she said in Turkish. "We were told an envelope came to the consulate, there was a powder inside, that it was dangerous, and that we were being sent home."
The Belgian Consulate, asked by CNN about the security incident, said police were investigating a substance found in an envelope sent there.
The air conditioning system in the consulate has been turned off, Semple reported. "And … anyone who was exposed to the package has been kept in that room, cordoned off from everyone else as a precaution."
The Canadian Embassy in Ankara, Turkey's capital, is also closed, but that's been attributed to shortened Friday hours not any threat.
On Thursday, Canadian Forces officials said they were assessing whether heightened security was necessary at bases after a shooting on Parliament Hill on Wednesday left an Ontario reservist dead. Also mentioned were installations abroad.
“We will carry on all our missions at home and abroad in a steadfast, resolute and vigilant manner, and serve our nation and her people,” said Gen. Tom Lawson, chief of Canada's defence staff, in a statement.
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