A notice was posted on the agency's website that says it detected "an internet vulnerability'' and took down many of its services, including electronic tax filing.
The services include ones such as "My Account,'' "My Business Account,'' "Netfile,'' "EFILE'' and "Auto-Fill My Return.''
The notice says people can still complete their forms, but will have to wait to file.
The Canada Revenue Agency headquarters in Ottawa is shown in 2011. (Photo: Sean Kilpatrick/Canadian Press)
A spokesman for the Canada Revenue Agency says the tax filing services were taken offline Friday as a precaution to protect Canadians' tax information.
Patrick Samson says the CRA isn't aware of any personal information being affected, but says the agency will monitor the situation.
"Digital services were taken offline as a precaution, not as the result of a successful hack or breach,'' Samson says in an email.
Digital services will remain offline until officials are satisfied there is no longer a security risk, he says.
The CRA website itself remains online as Samson says it was determined it wasn't a risk.
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