In an escalation of violence that could affect oil prices internationally, the Nigerian government says 21 soldiers from Cameroon were killed while patrolling an area housing oil facilities owned by Exxon and Shell. 

The government blames a well-known militant group for the incident, and the militants accuse the government of a cover-up.

The dispute follows a week of attacks from the militant group, MEND, which stands for the Movement to Emancipate the Niger Delta. The group claims it is fighting for a more just distribution of the country's billions of dollars of oil revenue. In just this year, it has been responsible for the kidnapping of more than 100 foreign oil workers and attacks against oil facilities in the Niger Delta region.

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On Monday, MEND's spokesperson, who calls himself Jomo, stated in an e-mail that the group "raided the Exxon Mobil Qua Iboe Terminal jetty in Akwa Ibom state of Nigeria," and that "our mission was to dispossess the military guards of all arms, ammunition and out-board engines at the jetty."

Calling the operation to protect the oil terminal "a success," representatives from Exxon said their facility was unharmed and MEND's attempted attack failed, according to media reports.

The Nigerian government claims that after the failed attack, the group went on to attack and kill 21 Cameroonian soldiers protecting oil facilities in the Bakassi peninsula, an oil-rich area of Cameroon, which borders Nigeria.

But Jomo disputes the Nigerian government's account. He states in the e-mail that "the murdered Cameroonian soldiers in Bakassi were carried out by the Nigerian military because of their perceived sympathy to our cause and their blind eye to a weapons route."         

He later goes on to accuse the government of trying to cover up their involvement by "executing some prisoners on death row to present their riddled bodies and some weapons to the media as the 'militants' killed in the shootout," a charge Nigeria's Director of Defense Information Col Solomon Giwa-Amu called "mindless and ridiculous."

Yesterday MEND claimed responsibility for sabotaging a Shell oil pipeline and threatened to start targeting non-oil facilities, like bridges, around the country. But the group said, "We will give a fore-warning to avoid casualties as our intent is to only bring down those symbols of oppression and injustice."

The increase in attacks comes after reports in late September that "Jomo" had been arrested and detained by the new Nigerian government which, he stated in the e-mail, was tantamount to "declaring war" with the group. Since then, both the number of attacks and the rhetoric from both sides has continued to escalate.

Nigeria is the sixth largest oil export country in the world, producing high-quality sweet crude oil, but has seen its production drop by as much as 25 percent since last year due to attacks on oil facilities.

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