Four Nigeria soldiers are missing and presumed dead after an attack by gunmen in the southern oil-rich Niger Delta creeks, the military and a state government said Friday.

The soldiers, among them a lieutenant-colonel who was commander of a unit, were ambushed and attacked not far from where four marine policemen were shot dead at a checkpoint on Thursday, the same day the military came under fire.

"The JTF has declared missing the four personnel reportedly attacked by the gunmen and have engaged local divers to search for their corpses," Timothy Antigha, spokesman for the special military unit, the Joint Task Force, told AFP.

Thursday's attacks took place on waterways in Nigerian President Goodluck Jonathan's home state of Bayelsa.

The governor of Bayelsa state, Henry Seriake Dickson, in a statement "commiserated with the families of the officers and men of the Nigerian military, police and civilians killed by pirates yesterday at the Brass and Ogbia waterways".

A militant group in the region, the Movement for the Emancipation of the Niger Delta (MEND), on Friday claimed it was behind the attack of the policemen. It gave no motive for the attack.

Antigha said the military were travelling in a civilian boat.

"They came upon a convoy of what we think are some renegade militants who opened fired on their very boat," Antigha said.

He said soldiers had been deployed to hunt down the attackers.

The JTF is deployed in the region to tackle crime, including oil theft and piracy.

It was not immediately clear how many civilians were also on the boat.

The boat driver, however, escaped, according to Antigha.

MEND militants claim to have been fighting for a fairer distribution of oil revenue in Nigeria.

A 2009 government amnesty offer for the militants greatly reduced the attacks after more than 25,000 ex-fighters laid down their arms.

Most of MEND's commanders and their fighters took up the amnesty offer, but MEND spokesman Jomo Gbomo said the group was never part of the deal.

Ivory Coast puts 28 paramilitary police on trial
Abidjan (AFP) March 2, 2012 - A military court in Ivory Coast put on trial Friday 28 paramilitary police accused of crimes in the period last year when former president Laurent Gbagbo tried to cling to power, a prosecutor said.

"These gendarmes, including a colonel, were close to Major Jean-Noel Abehi, former head of the armoured unit of the gendarmerie based at Agban in Abidjan," military prosecutor Ange Kessi told AFP in the economic capital, where the court is sitting.

Abehi, a former Gbagbo ally who is currently on the run, was convicted in August last year by a military tribunal. He is wanted for crimes committed between December 2010 and April 2011, when Gbagbo refused to accept that he had lost a presidential election and the west African country briefly plunged back into civil war.

The violence, which pit pro-Gbagbo supporters against former rebels and others who backed the internationally recognised winner of the election, Alassane Ouattara, claimed at least 3,000 lives.

The gendarmes are accused of public order offences and disobeying military orders, Kessi said.

Nine soldiers from the Republican Forces of Ivory Coast are also due to go on trial for "atrocities against the population, murder" and other offences alongside the paramilitary police.

Kessi said Thursday that the military court would handle "almost 137 cases covering various categories of crime during the Gbagbo era " in a year-long sequence of trials, which would come up as the investigations were closed.

Gbagbo, who was finally arrested by forces loyal to Ouattara, is currently jailed at the International Criminal Court in The Hague, where he faces four counts of crimes against humanity.

The ICC said last week it had given its prosecutor the green light to extend a probe into war crimes in Ivory Coast back to 2002, when a failed coup against Gbagbo left the country divided.

Last October, military courts announced charges against dozens of soldiers of the toppled regime, of whom 40 are currently in detention.

They include General Bruno Dogbo Ble, former commander of the feared Republican Guard, and Admiral Vagba Faussignaux, ex-chief of the navy, who were both seen as stalwarts of Gbagbo's 12-year rule.