Militias in the Niger Delta have long threatened Nigeria's economic security, but the nature of the crisis has evolved in recent years. Organised crime has replaced insurgency as the pre-eminent threat to the country's oil revenues. Though piracy and kidnappings are still a major concern, oil multinationals are losing more money from pipeline vandalism than from any other form of attack by local armed groups.
The Nigerian government relies on crude oil for 70% of its revenue, but oil thefts and outages related to instability in the Niger Delta are causing severe disruption to the operations of multinational oil companies. In August 2013 the Nigerian accountant-general noted that the country's revenues had plummeted by 42% during the previous month. Reports that Angola had produced more oil than Nigeria in May 2013 prompted speculation as to whether it could soon be eclipsed as Africa's largest oil producer.
Nigeria's crude-oil reserves stand at 37.2 billion barrels, and the majority of these lie within the Niger Delta. The region's current insecurity is the result of a long-running struggle by local groups for control of its abundant resources. The kidnappings and incidents of piracy for which the area was once notorious do still go on, but have declined since 2006. Oil theft, or 'bunkering' as it known locally, poses the greater security threat now.