A hitherto unknown militant group, calling itself the Niger Delta Avengers, said it had dynamited the trunkline linking the Dutch-British Shell company's Bonny terminal and the Brass export terminal of the Italian company Agip.
Earlier, the group had blown up gas and crude oil pipelines belonging to the Nigerian National Petroleum Corporation (NNPC) in Delta State near the city of Warri.
Nigeria's oil production had already fallen from a projected 2.2 million barrels per day (bpd) to 1.4 million bpd before the latest string of attacks on the oil industry in southern Nigeria, including three within the past week on facilities of the US oil company Chevron.
This AFP file photo taken on March 22, 2013 shows an aerial view of Shell Cawtharine channels at Awoba in the Niger Delta.
The militants have given oil companies a May 31 deadline to leave Nigeria's southern, oil-producing Niger Delta.
"Watch out something big is about to happen and it will shock the whole world," the the Niger Delta Avengers (NDA) warned Saturday, addressing international and indigenous oil companies and Nigeria's military.
The NDA has intensified attacks in recent months, pushing oil output to its lowest in more than 20 years and compounding the problems faced by Africa's largest economy.
The group claims it is fighting to win a greater share of oil profits for the nation and protect the environment from pollution caused by these oil companies.
Local community leaders and non-violent environment activists have reportedly sided with the militants.
They say residents of Niger Delta support their demands for a greater share of the country's oil wealth.
Oil pollution has destroyed the livelihoods of hundreds of thousands of farmers and fishermen in the region.
Several companies have evacuated some of their workers while the government has deployed thousands of troops to guard oil installations, Press TV reported.
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