By Tife Owolabi
YENAGOA, Nigeria (Reuters) - Nigerian militants have ambushed a police boat in the oil-producing Niger Delta region, leaving 12 officers missing and presumed dead, security officials said on Sunday.
The ambush came days after the Movement for the Emancipation of the Niger Delta (MEND), the main delta militant group prior to a 2009 amnesty, threatened to restart attacks in retaliation for the jailing of leader Henry Okah by a South African court.
Police Commissioner Kingsley Omire said the ambush was carried out by militants once loyal to Kile Selky Torughedi, who headed MEND's southern wing, but denied there was a link to the threat by the group, whose attacks cut oil production in Nigeria by around half before the amnesty.
He instead blamed a dispute between the gunmen and the government over their amnesty payments - underscoring the fragility of the peace that has been achieved in the delta by paying off thousands of militants to silence their guns.
The government is keen to wind the amnesty payments down but fears that as soon as it does the militancy will restart.
Omire said the boat carrying 50 police officials was heading to a funeral late on Friday when it developed engine problems in one of the winding creeks of the swampy delta region that is home to Africa's biggest oil industry.
"The craft developed engine problem was now isolated and the officers became soft target for some hoodlums, who we have confirmed were part of a militant group that was supposed to be enjoying an amnesty," Omire said.
A Nigerian security source, who could not be named, said the 12 were very likely all dead. Omire said all others on the boat were safe.
Any resurgence of militant activity would be a blow to President Goodluck Jonathan, who helped negotiate the amnesty and who is from the same Ijaw ethnic group as most of the militants. His administration's security forces are already stretched by an Islamist insurgency in the north.
It would also be a major headache for multinational oil companies such as leading operator Royal Dutch Shell, already contending with industrial scale oil theft by armed gangs that saps up to a fifth of Nigeria's 2 million barrel-a-day output, according to some government estimates.
While attacks in the Niger Delta region have been fewer since the amnesty, kidnapping, piracy, large-scale oil theft and pipeline sabotage still occur on a near daily basis.
However, MEND threatened on Thursday to restart "a plague of attacks" in an emailed statement signed by Jomo Gbomo, a pseudonym used by the group, in response to Okah's jailing.
He was sentenced to 24 years in prison on March 26 for masterminding two deadly car bombings in the Nigerian capital in 2010 that killed at least 10 people.
MEND has been largely inactive since most of its militants agreed to the amnesty, although the group claimed an attack on crude oil pipeline owned by Italian oil and gas group Eni in April last year.
(Writing by Tim Cocks; Editing by Alison Williams)