Local anger was most famously mobilised in the Ogoni area by opposition politician Ken Saro-Wiwa, but in all parts of the Delta protesters have blocked access roads, occupied production platforms and-on occasion-sabotaged pipelines.

BBC: Oil wealth: An unequal bounty

The Movement for the Survival of the Ogoni People (Mosop) and the Wiwa family have exchanged a series of angry press releases, in a feud which appears to hinge on an invitation to foreign forensic experts to exhume the bodies.

BBC: Dispute over Ogoni activists' reburial