Abattoir Blues. The 22nd DCI Banks novel from The Master of the Police Procedural

Two missing boys. One fatal shot. When DCI Banks and his team are called to investigate the theft of a tractor from a North Yorkshire village, they're far from enthusiastic about what seems to be a simple case of rural crime. Then a blood stain is found in an abandoned hangar, two main suspects vanish without a trace, and events take a darkly sinister turn. As each lead does little to unravel the mystery, Banks feels like the case is coming to a dead end.
Until a road accident reveals some alarming evidence, which throws the investigation to a frightening new level. Someone is trying to cover their tracks - someone with very deadly intent .