Oil giant Shell has been covering up catastrophic oil spills in the Niger Delta by blaming them on sabotage by local people, according to a leading human rights group.
Those living in Nigeria's oil-rich delta are suffering a "human rights tragedy" inflicted by decades of environmental damage caused in large part by Royal Dutch Shell, Amnesty International claimed.
The report Petroleum, Pollution and Poverty in the Niger Delta, released yesterday in Abuja, says the contamination has damaged farmland, destroyed fish stocks and polluted the air and water, while oil companies' response has been misleading or inadequate.
Shell is the largest operator in the region and has long argued that insecurity in the Delta - where its operations are routinely attacked by militants - is responsible for much of the spillage and resultant environmental destruction.
However, the new research suggests the oil giant has exploited the instability and lack of oversight to cover up oil spills caused by its own out-of-date or faulty equipment.
"Oil companies have huge influence over the investigation of oil spills and other industry-related damage," the report alleges.
"The companies frequently designate the causes of spills, and communities cannot hold them accountable when they disagree."
Independent auditors estimate that up to 13 million barrels of oil have been spilt in the Delta, an amount equivalent to an Exxon Valdez disaster every year for 40 years.
The Niger Delta is home to some 31 million people, the majority of whom live in abject poverty despite the $600bn in oil revenues generated since extraction began in 1958.
Nigeria's own watchdog reports that there are 2000 current spills, the majority of them from Shell operations.
The report highlights a spill at Bodo in Ogoniland last August caused by a pipeline leak. Oil poured into the swamp for weeks covering the area in a thick slick and killing fish.
Local people's access to food and water was devastated. Shell has disputed the circumstances of the spill and, as of last month, had not cleaned it up.
Emergency help in the form of 50 bags of rice, 50 bags of beans, 50 bags of garri, 50 cartons of sugar and 50 cartons of dry peak milk was rejected as "insulting and provocative" by the community of 69,000 people.
Shell's environmental legacy in the Niger Delta has been back in the spotlight since the company paid out $15.5m in compensation last month to relatives of Ken Saro Wiwa, a Nigerian environmentalist executed in 1995.
Campaigners have called on Peter Voser, the company's new CEO, to stop "greenwashing" and implement real change at the oil giant.
"Shell attempts to paint itself as a sustainable company when in reality it is the dirtiest oil producer of all," said Paul de Clerck from Friends of the Earth International.