The BBC has uncovered evidence that a secret deal was made to allow hundreds of ISIS fighters and their families escape from Raqqa, under the watch of the U.S.- and British-led coalition and Kurdish-led forces who control the city.

A convoy included some of IS’s most notorious members and – despite reassurances – dozens of foreign fighters. Some of those have spread out across Syria, even making it as far as Turkey.

The BBC talked to dozens of drivers who were involved in convoying ISIS fighters and their families (and lots of weapons) out of Raqqa, the Islamic State’s de facto capital, once upon a time, as well as the men who negotiated the deal.

The drivers are angry now because none of them have been paid.

“We were scared from the moment we entered Raqqa,” one says. “We were supposed to go in with the SDF, but we went alone. As soon as we entered, we saw IS fighters with their weapons and suicide belts on. They booby-trapped our trucks. If something were to go wrong in the deal, they would bomb the entire convoy. Even their children and women had suicide belts on.”

Why it’s on our radar: Information in this article helps satisfy Priority Intelligence Requirement 2: What is the current situation report and risk of war in each of the four flashpoints?