The Senate was placed on alert Monday after an "unknown white powder" was received at the offices of two separate members, though it later turned out to be non-toxic.
Mike McDonald, director of the Senate Protective Service, issued a note alerting all members and staff of the upper chamber that envelopes with the return address "Ottawa shooting" were secured after being picked up at two offices.
UPDATE: 4:36 p.m. -- Sen. Claude Carignan's office has confirmed in a news release that his was one of the offices that received an envelope.
A separate note showed that all tests of the white powder by the RCMP turned out negative for the "presence of any harmful substances." Where the envelopes came from is still under investigation.
In the meantime, parliamentary staff and politicians have been warned to be careful with handling suspicious packages, to not open, move them or "handle [them] excessively" and, when a substance is found, not to "disturb" or contaminate it.
This is the second recent instance in which politicians have received suspicious envelopes.
Earlier this month, envelopes with white powder were found at the riding offices of four Conservative cabinet ministers from Quebec.
The offices belonged to ministers Denis Lebel, Maxime Bernier, Christian Paradis and Steven Blaney.
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