RCMP Sgt. Peter Thiessen says it's all part of a scheduled exercise designed to test the response to an emerging threat.
He says even social media users should be aware of the exercise because tweets or posts could be made by mock witnesses or victims of the emergency, giving police a chance to test their reaction to such information.
Thiessen says any mock tweet will carry an alert identifying it as part of an exercise, and he says pedestrians around UBC's Agronomy and Main Mall roads should not be anxious if they see emergency response teams, or what appear to be victims in triage areas outside certain buildings.
The drill, involving as many as 200 responders from agencies including the RCMP and Vancouver Police Department, is due to wrap up at about 1 p.m.
UBC spokeswoman Lucie McNeill says the exercise allows the University to fine-tune its response to emergencies and how it works with the RCMP and other partners.
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