“We have never experienced something like this,” said the director of the Norway-based NGO Iran Human Rights (IHR), which has been tracking rights violations in the Islamic republic for some two decades.

As a fragmented picture of the anti-government protests that peaked in early January emerged, IHR and other NGOs set out to verify the reports of thousands of deaths – painstaking work they are still undertaking weeks later.

“Based on the witness testimonies, all the information we have managed to receive from different parts of the country, it’s an unprecedented mass killing at a scale that we haven’t seen before,” he told AFP.

Along with the sheer numbers, NGOs say their task has been complicated by the internet shutdown, manipulated content and threats against sources inside Iran.

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