Kenya's Night Runners

Every night, in villages across Kenya, elusive figures sneak around in the dark, throwing stones and carrying out small acts of vandalism. They don't attack anyone or steal anything. Their only aim appears to be frightening people. They're called 'Night Runners' and they've been part of Kenyan culture for centuries. People used to believe they were demonic spirits. For Our World, Kenyan journalist Tom Odula, has tracked down some of them, and finds out why they terrorise their neighbours, what happens to them when they're caught and why they can't seem to stop.