Light shed on the Five Eyes network when former NSA contractor Edward Snowden published thousands of documents from inside the intelligence agency.
We know that the NSA and GCHQ have worked together to obtain the contact lists and address books from hundreds of millions of personal email and IM accounts as well as webcam images from video chats of millions of Yahoo users.
In 2015 it was said New Zealand conducted mass surveillance against its Pacific neighbours, including gathering calls, emails, and social media messages.
wired.co.uk/article/five-eyes-sue-us-government-privacy-international