From soldiers who surrendered in battle to civilians perceived to be sympathetic to the Assad government, Syria’s various rebel factions take a lot of prisoners. Many of them don’t live very long, however.

That’s because, as a new human rights report from Amnesty International is reporting, Syrian rebels regularly end up summarily executing their detainees, with some groups releasing videos of the executions after the fact to brag about them.

It is just one of many examples in the new report (pdf) detailing the growing number of human rights violations by the Western-backed Syrian rebels, including torture and arbitrary detentions.

Free Syrian Army officials didn’t dispute the report, but denied that it was a problem, insisting that revenge killings “happen in wars all over the place” and that each of these cases should be treated as “individual cases” instead of the broad trend that it indeed is.