Canadian Visitor Visa Help

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Hello Everyone

I am living in Canada as a Permenant Resident.

My Parents are Planning to Visit canada. both of them are Tamilnadu State Government employees.If they are applying for a Visitor Visa to canada is it required to get NOC from the Government.please advice.

Can you please explain me what are the procedures for applying NOC or will it be sufficient to get a Leave Sanction Letter.

I checked in the internet i couldn't get any information about NOC. so please provide me any links.

waiting for the reply

Thanks

Regards
Vidhya