Security agents on Tuesday found 11 bodies of policemen out of the 12 declared missing at the weekend in the southern Bayelsa state, police and army spokesmen said.
State police spokesman Alex Akhigbe said that the bodies were taken to a morgue in the state capital Yenagoa.
Witnesses said some of the bodies recovered along the creeks and waterways of the oil-rich state were burnt beyond recognition, mutilated and stripped of their uniforms and rifles.
The Friday attack came just two days after a militant group in the Niger Delta region, MEND, allegedly threatened to resume attacks over the conviction of presumed leader Henry Okah in South Africa. But police say the attack was as a result of a dispute between an ex-militant and his gang over improper distribution of a 2009 amnesty payment, and alleged abandonment.
Authorities said the attack occurred while police were escorting the ex-militant, who had relocated to Abuja since the amnesty deal was struck, to his mother’s burial.
Bayelsa police commissioner Kingsley Omire had said one of the police boats broke down on the way and was a “soft target”.
MEND had threatened attacks on the country’s oil facilities for Nigeria’s role in the conviction of the supposed leader Henry Okah who was sentenced to 24 years in prison over twin car bomb attacks on Independence Day in Abuja in 2010.