The police chief in a small town in Pennsylvania and two of his officers are being held in prison accused of having organised a cover-up following a brutal attack on an illegal Mexican immigrant by a group of white high school students which ended in the Mexican man’s death.

The indictments bring the full weight of US federal law down on Shenandoah, a declining rustbelt town of about 5,000 people 80 miles north-west of Philadelphia. The allegations also cast light on the relationship between senior officers and the teenagers they were supposed to be investigating. [bp]