(sirens wailing) >> ramita navai: january 2020. for months, iraqis had been taking to the streets in nationwiderotests like this over the dire conditions in the country. (indistinct yelling) as the demonstrations grew, their anger turned to a new target. >> (chanting in arabic): >> navai: iranian-backed shia militia groups that were operating with increasing impunity throughout iraq. protesters set militia bases on fire, and the militias fought back. they were accused of unleashing a wave of assassinations against their critics. (car horn honking) ♪ ♪ i traveled into iraq in september 2020 to investigate the reports of growing violence by the shia militias, groups that had once fought heroically to defend the country from isis, but have since expanded into a powerful political and economic force. i headed to the north, where we'd made contact with a group of yng activists who'd gone in hiding after criticizing the militias during the protests. they'd all fled the southern city of basra. only two would show their faces on camera. >>

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