A day after armed men invaded a residential compound near the community of Eket, in Nigeria's oil-rich eastern delta, killed two Nigerian guards and abducted at least five foreign oil workers including three Britons and two Malaysians, life seemed to have gone back to normal. The oil workers were taken from a compound close to the operational base of ExxonMobil, which exports about 800,000 barrels a day from Africa's top oil producer. Violence in the delta is rooted in poverty, corruption and lawlessness. Most inhabitants of the wetlands region, which is almost the size of England, have seen few benefits from five decades of oil extraction that has damaged their environment. Resentment towards the oil industry breeds militancy, but other factors such as the struggle for control of a lucrative oil smuggling business and the lure of ransoms also lie behind the violence. Speaking to the press the youth leader of the Akala Olu community in Eket, John Ayike, said the increase in militancy in the delta is as a result of hunger and deprivation of the people of the basic needs of life. "A hungry man is an angry man, the people are hungry, they don't have to eat and there's no alternative than to carry arms, that's why the increase in militancy in the Niger Delta," Ayike said. All Nigerian staff of a Royal Dutch Shell contractor abducted on Monday (October 2) had been released by Wednesday. 10 soldiers were believed to have been killed in the raid by militants on a convoy of boats supplying oilfields in a different part of the delta, during which the Royal Dutch Shell workers were abducted. About 70 gunmen in speed boats attacked the barges carrying fuel and other supplies to Shell facilities in the remote Cawthorne Channel in Rivers state in the Niger Delta. The series of attacks ended a period of relative quiet in the Niger Delta, which accounts for all oil output from the world's eighth biggest exporter. One sixth of Nigeria's production capacity has been shut down since February following a wave of militant attacks on oil facilities that month. Adding to the sense of unease, the United States Consulate in Nigeria said in a circular on Wednesday that militants may target Bonny Island, a major oil and gas export hub in Africa's top oil producer. The threat of attacks on other installations has escalated substantially over the past few days with five separate attacks in eastern Niger Delta in three days. Supply disruptions from OPEC member Nigeria have contributed to several spikes in world oil prices this year.