Privacy Commissioner John Edwards was forced to cancel a speech by Una Jagose, the acting director of the Government Communications Security Bureau, after two protesters interrupted the event, claiming the spy agency was involved in drone attacks across the globe.
Ms Jagose was to deliver a speech on cyber-attacks at the National Library in Wellington as part of the commission's technology and privacy forum when the two Stop the Spies protesters unfurled a banner and refused to leave.
She declined to speak with the banner in front of her, forcing Mr Edwards to cancel the session.
Protester Valerie Morse said the forum was a "Five Eyes propaganda exercise", referring to the intelligence-sharing alliance between New Zealand, Australia, the US, Canada and UK, which sought "to legitimise an agency which is fundamentally contrary to the interests of most people in this country and indeed most people of the world".
She claimed the GCSB was involved in drone assassinations and attacks in Afghanistan and Pakistan.
"Why is the privacy commissioner, who is tasked with upholding the privacy of ordinary people in this country hosting the single most secretive agency in this country," she told a crowd of some 80 people.
Mr Edwards thanked the two protesters for their contribution and said there was the opportunity for questions after Ms Jagose's speech, but was forced to call off the event when they refused to take down the banner.
"The views of a wide range of members in our community are important any discussion about the appropriate limits of state power," Mr Edwards said.
The commissioner said the event would be rescheduled.