What is "popobawa"

Popobawa, also Popo Bawa, is the name of an evil spirit, or shetani, which is believed by residents to have first appeared on the Tanzanian island of Pemba. In 1995, it was the focus of a major outbreak of mass hysteria or panic which spread from Pemba to Unguja, the main island of the Zanzibar archipelago, and across to Dar es Salaam and other urban centres on the East African coast.