Shannon Matthews - The Plot Thickens

The Shannon Matthews story takes another twist, as she's not returned to her parents and a relative of her stepfather is arrested. Somehow I don't get the impression of a classic 'held-against-will' scenario. All very odd. But it was this that got me :

It emerged in the course of the inquiry that an astonishing 1,387 registered sex offenders live within a 20-mile radius of the nine-year-old's family home in Dewsbury Moor, West Yorkshire.

Pi * R2 - thats about 1300 square miles - so about one sex offender per square mile in West Yorkshire.