They were trying to reach Europe when they were forcibly turned back at sea. The Libyan authorities have rounded up thousands of refugees and migrants over the last week, holding them in detention centres where conditions are described as "inhumane". (Subscribe: https://bit.ly/C4_News_Subscribe)
In the last few hours, several hundred people have escaped en masse from one of Tripoli's largest camps. There are now fears for their safety, amid reports of indiscriminate shooting.
Viewers may find this report distressing.
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