In pictures: Fighting for Nigeria's oil

Mr Dokubu-Asari says he has 2,000 followers, although the BBC saw no more than 30 or 40 men.

They are armed with automatic rifles, which they proudly display. They also claim to have heavier weapons.

It is not clear what Mr Dokubu-Asari is really fighting for.

But the fact that he is able to claim ownership of towns, head a militia and evade capture shows the extent of the Delta's problems.

Text and six photos: The BBC's Anna Borzello