Rare look at an illegal oil refinery
2 August 2012 Last updated at 01:42 BST
The Nigerian authorities say they are clamping down on the illegal trade in crude oil.
The Nigerian government says it is losing up to $1bn a month as a result of the theft in the Niger Delta.
Whilst some of the oil is refined locally, much of the stolen crude is taken out on barges to ships waiting off the coast.
But with politicians and the military known to be benefitting from the trade, it seems unlikely that the practice will be be stopped.
The BBC's Nigeria Correspondent Will Ross got a rare look at one of the illegal refineries.