In the days after the worst mass shooting in Australia since Port Arthur, a wave of misinformation spread across social media. A video of Australian federal police commissioner Krissy Barrett claiming four Indian nationals had been arrested, with a Guardian watermark on screen, was in fact a deepfake made from a genuine video of a press conference Barrett had given on 18 December. The video was flagged by online factcheckers, but not before being watched hundreds of thousands of times. As Guardian Australia's technology reporter Josh Taylor explains, these deepfakes are only getting easier to make

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