Although most of the ordnance came from old, unreliable stocks and failed to explode, the attacks were a clear violation of the no-fly zone. NATO immediately looked for ways to respond, but its forces were not permitted to carry out operations in Croatian airspace, and due to Bihać's proximity to the border, Serb aircraft could attack into Bosnia, then cross back into Croatia before being intercepted.[21] As such, NATO was powerless to stop the incursions. In recognition of the situation, the Security Council passed Resolution 958, which allowed NATO aircraft to operate in Croatia.