From the BBC Fighting for Nigeria’s oil wealth:

The Niger Delta, a region the size of England, is littered with violence and gas flares – the offshoot of oil extraction – whose roar and heat you can feel for hundreds of metres around.

The flares have become symbols of the region and the paradox that exists in an area where you find one of the world’s richest oil regions alongside some of the poorest people.

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With unemployment at 90%, many people of the Delta are tempted to join the criminal gangs who terrorise the area, kidnapping foreign oil workers and launching raids on oil platforms.
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Maintenance of the gangs, their boats and weapons is expensive and is funded by the theft of oil on a huge scale – up to 200,000 barrels a day.
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The gangs are well-armed and the Joint Task Force is ill-equipped for the challenge.

They’ve managed to seize only a few of the barges used to ferry the stolen oil to huge tankers waiting offshore to take it on to the world’s refineries. It’s a huge and sophisticated operation on an international scale.

For more information on oil piracy see the Christian Science Monitor, PBS Newshour, and the BBC who write “Nigeria’s oil production has been cut by around a fifth since 2006, partly as a result of the violence by criminal gangs and militants. “