The Movement for the Emancipation of the Niger Delta (Mend) stated in an email released it had launched an "oil war" on the government
The Movement for the Emancipation of the Niger Delta (Mend) have "declared war" on the government after battling security forces guarding facilities. Mend
was responding to attacks by the military.
Several Mend attacks had repelled with both sides saying their opponents suffered heavy losses.
Mend' s fighting a bigger part of the area's oil wealth and the violence has cut Nigeria's oil output by more than 20%.
Mend militants are the largest of several armed groups active in the delta region. They have kidnapped foreign oil workers and sabotaged oil installations and pipelines.
Nigerian President Umaru Yar'adua is under pressure to crack down on the militants and make the delta safer for international oil firms.
Mend, in an email, said it had launched an "oil war" on the government in response to what it described as unprovoked aerial attacks on its bases in the Niger Delta.
"The operation will continue until the government of Nigeria appreciates that the solution to peace in the Niger Delta is justice, respect and dialogue," the group said.
An oil platform at Kula, operated by oil giant Chevron, was among the facilities targeted and Mend reports 22 Nigerian troops had been killed in the attack.
A Nigerian military spokesman said they had repelled an attack on an oil platform operated by the US company, Chevron and stated the militants had suffered heavy casualties.
The Niger Delta region is plagued by corruption and poverty but remains the source of most of the Nigerian government's income.