Three top Nigerian militants along with thousands of supporters surrendered on Sunday, on the last day of amnesty offered by the government to rebels fighting for control for oil in resource-rich Niger Delta region.
The Nigerian President Umaru Musa Yar'Adua had granted a 60-day grace period to militants.
A top militant Government Ekpemupolo alias Tompolo who heads the Federated Niger Delta jaw Communities (FNDIC) has disarmed.
Tompolo's surrender came immediately after a top leader of the main militant group, Movement for the Emancipation of the Niger Delta (MEND), Farah Dagogo accepted the amnesty offer.
Farah Dagogo, a former commander of the country's main militant group, said that he and other field commanders in Rivers state have surrendered all of their weapons.
Meanwhile, MEAD told PTI in a statement it has already "replaced the commanders who have surrendered". The group has said it would not accept an amnesty deal.
MEND said its next phase of campaign would commence soon. Another militant leader Ateke Tom and around 5,000 militants disarmed at a beach ceremony. Observers now fear a strengthened onslaught by the government groups or persons that did not accept the amnesty.
The unrest has cut Nigeria's oil production by a million barrels a day, allowing Angola to surpass it as African continent top oil producer.