With foreign airstrikes becoming an increasing problem in ISIS territory, the Islamist group’s leadership is stepping up efforts to track down spies working for the US and its allies.

Today, ISIS announced it is offering $5,000 to anyone who can capture an informant or provide information leading to such a capture. Fliers announcing the deal have been reported around ISIS territory in Syria.

While they will no doubt eagerly take any spies for foreign powers, the effort seems in particular to find the spotters on the ground helping US warplanes pick out targets to bomb.

Such efforts are risky. Early in the US occupation of Afghanistan they offered similar cash for enemies campaigns, and it fueled a rash of kidnappings by people hoping to profit from the scheme. It is unclear how ISIS will verify that the captives are actually spies.