Envelopes containing white powder were sent to the offices of Canadian senators, according to reports. Officials have since declared the substance to be "non-toxic" according to CTV.
The envelopes that arrived via postal mail were marked with the words "Ottawa Shooting."
On Oct. 22, 2014, Parliament Hill in Ottawa, Canada, was locked down after a gunman killed Corporal Nathan Cirillo at the National War Memorial and then entered a nearby building.
The shooter, Michael Zehaf-Bibeau, went into the building where members of Parliament were meeting. He was cornered and killed by the commons sergeant at arms.
Envelopes containing white powder sent to Canadian senators' offices; return address reads 'Ottawa shooting' - CTV… http://t.co/jTuVbsQXCT
— Breaking News (@c__1651421) March 23, 2015
