Nigeria's oil rebels said they attacked an offshore platform operated by Royal Dutch Shell, the latest attack against oil companies in the oil-rich southern region.
According to a statement e-mailed to journalists, Nigeria's largest militant group, the Movement for the Emancipation of the Niger Delta, known as MEND, said it sabotaged Shell's Forcados offshore platform in Delta state. The group said at least 20 soldiers were killed.
There was no immediate confirmation from the military. Shell said it was "aware of reports of an incident."
The company suspended most of its operations in the western Niger Delta after militants' escalated attacks on the oil industry in retaliation for an army offensive that started in mid-May.
MEND has rejected recent overtures from the government, including the offer of a blanket amnesty to militants who lay down their arms and give up their campaign. Some militant leaders have reportedly accepted the amnesty in principle. The group is seeking direct talks with the government and the release of one of its leaders, Henry Okah.
A spokesman for the military Joint Task Force deployed to the oil region, Colonel Rabe Abubakar, said rebels who have been attacking oil facilities and personnel in the Niger Delta in the past three and half years should take advantage of the offer.
"Some of them [militants] have started realizing the importance of peace. They have started realizing that, 'Look, we cannot continue in this direction because it would carry us nowhere'. I believe you must have heard a few of them who decided to drop their arms and accept the amnesty," he said. "We are still calling on them to seize this opportunity of amnesty by the federal government in order to move this region forward. They should know that peace and security are two inseparable elements for development," he added.
The government estimates that as many as 20,000 fighters and criminals could participate in the amnesty program, which involves disarmament, education, and rehabilitation.
Nigeria's petroleum infrastructure is threatened by militias driven by anger the government and international oil companies are not sharing the oil wealth with the impoverished residents of the Niger Delta.
Armed attacks in the region that produces nearly all of Nigeria's oil has cut production by more than 20 percent since early 2006.