Virginia shooting: How thousands watched murder video by mistake
Thousands saw the moment two US journalists were killed because of a feature that automatically plays video on Facebook and Twitter.
Footage of Alison Parker and Adam Ward being shot was posted to social networks by the gunman. His accounts were quickly suspended, but it was already too late for those who saw the video and complained about it online.
Almost 17,000 tweets mentioning "autoplay" were posted within 24 hours.
Produced by: Anne-Marie Tomchak and Henry Wilmer.
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