Gunmen in four speed boats targeted the military checkpoint in southern Bayelsa state on Friday, authorities said.
Soldiers destroyed the camp in neighbouring Rivers state and are now trying to track down others who escaped, according to a statement from the Joint task Force (JTF) in the Niger Delta. Other items recovered included three speed boats, communication gadgets and generators, source said.
It is not yet clear who was behind the attack.
An amnesty in 2009 for tens of thousands of oil militants – who receive a monthly stipend from the government – stemmed the level of violence in the region.