From the RCMP Canadian Firearms Program website:

The Zoraki Models 914 and 925 blank firing pistols have been identified, based on criteria set out in the Criminal Code, as prohibited firearms. Businesses in possession of either firearm must register the firearm, providing they are licensed to do so, or surrender the firearm to law enforcement agencies. Individuals have no option but to surrender the firearm.

In the notice posted on the Canadian Firearms Program website, the RCMP explains the implications to individual firearms owners, businesses and police agencies.

Implications for individual owners:

Individuals who are currently in possession of either blank firing pistol must surrender or dispose of these blank firing guns by contacting either the local police or the provincial Chief Firearms Officer immediately to make the necessary arrangements.

Implications for businesses:

This is a public safety concern because these firearms are sold by businesses in Canada, and unlicensed individuals and businesses may be in possession of unregistered prohibited firearms.
Businesses in possession of these firearms must either register the firearm, provided they are licensed to do so, or surrender the firearm to a law enforcement agency.  Individuals must surrender them.

See original RCMP notice here.