The Jamestown Foundation's Terrorism Focus, 6 Jul 07:

Nigeria's Cults and their Role in the Niger Delta Insurgency
In Nigeria's delta region, various militant groups continue to attack multinational energy interests by blowing up infrastructure, siphoning oil and gas from pipelines and kidnapping expatriate energy staff. Additionally, these groups often attack Nigerian security services. The origin of the militant groups in the delta today can partially be explained by the evolution of Nigeria's cult groups, more generally known as confraternities. Nigerian confraternities were largely the precursor to many of the militant groups in the delta. While confraternities began in the country's universities, these gangs eventually spread to the streets and creeks of the energy-rich delta region....