LAGOS, Nigeria -- Soldiers raided three militant camps Wednesday hidden in the winding creeks of Nigeria's oil-rich and restive southern delta, seizing heavy weaponry in an attack rebels claimed killed more than 100 people.
The attack started Wednesday afternoon in Delta state, an oil-producing state in the middle of Niger Delta, military spokesman Lt. Col. Timothy Antigha said.
Militants in the Niger Delta have attacked pipelines, kidnapped petroleum company employees and fought government troops since 2006. The attacks cut drastically into crude production in Nigeria, an OPEC-member nation that is crucial to U.S. oil supplies. Production has risen back to 2.2 million barrels of oil a day, in part due to many militant leaders and fighters accepting the amnesty deal.
However, not all have been pacified. The main militant group in the region, the Movement for the Emancipation of the Niger Delta, has promised to carry out new attacks after claiming responsibility for kidnapping seven expatriate workers in November from offshore oil rigs operated by London-based Afren PLC and Exxon Mobil Corp. The group, known by the acronym MEND, also claimed a dual car bombing that killed at least 12 people and wounded dozens more during an Oct. 1 independence celebration in Nigeria's capital, Abuja.
The government has taken a hard line on militancy in the southern delta since the car bombing. Securing the delta remains vitally important to President Goodluck Jonathan, who hails from the region, as he faces election next year.
Soldiers attacked three camps operated by fighters loyal to militant leader John Togo, who reportedly had accepted a government-sponsored amnesty deal last year but later abandoned it, Antigha said.
He said the fighting continued into Wednesday night, as soldiers recovered anti-aircraft guns, rocket-propelled grenades, automatic rifles and dynamite from the camps.
A statement sent to journalists Wednesday night from a little-known militant group calling itself the Niger Delta Liberation Force claimed more than 100 people died during an attack -- the majority of them civilians. The group's account of the attack could not be immediately verified.
Antigha acknowledged there may have been casualties in the attack, but declined to comment further.
Analysts say the push to pacify the delta will test the limits of the president's power.
"The Niger Delta campaign is now testing his ability to protect Nigeria," said Thompson Ayodele, executive director of the Initiative for Public Policy Analysis in Lagos. "If he fails his political opponents will capitalize on it, saying that he is a man who is not prepared for the job."
During an operation last month, the military managed to free 19 hostages, including seven foreigners. The man accused of masterminding the kidnappings, Otonyemie Kuna, 25, known in the delta as "Obese," has been arrested and faces charges in the attacks, Rivers state police spokeswoman Rita Inoma-Abbey said Wednesday.
Meanwhile, the federal government has announced more than 6,000 militants who missed the deadline last year to join the amnesty now will be included in the process after Jonathan gave his personal approval. That drew a retort from MEND, which promised to carry out new attacks just as the nation's oil industry has recovered and a presidential election draws near.
"This desperate action shows a confused individual, bent on looting the nation's treasury," the militant group said in a statement sent to journalists.
Associated Press writers Yinka Ibukun in Lagos and Bashir Adigun in Abuja, Nigeria, contributed to this report.