The Nigerian rebel group the Movement for the Emancipation of the Niger Delta, MEND, says it will take up arms again and resume attacks on oil production facilities. The group had called a cease-fire in July after Nigerian President Umaru Yar'Adua offered an unconditional amnesty and released one of MEND's main leaders Henry Okah. The government says 8,000 MEND commanders and soldiers have taken advantage of the amnesty and turned in their weapons.

However MEND has dismissed the amnesty as a "charade" and says that the government purchased many of the weapons it said had been turned in by rebels.

The attacks against the oil installations, which began three years ago, have reduced Nigeria's oil production from 2.6 million barrels a day to 1.7 million barrels. Earlier this week, Royal Dutch Shell CEO Peter Voser announced that onshore oil production has fallen heavily due to violence in the Niger Delta. "I think we are now at 120,000 barrels per day and we used to be close to 300,000."

MEND says the revenues from oil drilling do not reach the local population and have also devastated the region's natural environment.