[ This report does not necessarily reflect the views of the United Nations]

In the past two decades, the multinational corporations producing Nigeria's oil in the impoverished southern region have grown used to disruptions caused by protests or sabotage by locals who feel dispossessed of their oil wealth by the central government.

But in the past 14 days Nigeria has been confronted by something different: militants vowing to cripple oil exports and kidnappers with political demands. One new militant group has said it has now resolved to take control of the region's oil resources by force.

We're certainly facing a more intense level of violence and it's very disruptive to our operations,・one industry source said on condition of anonymity. We're really shocked by the amount of violence unleashed on Benisede [a facility recently attacked]. It was quite ugly.

Armed groups frequently take oil workers hostage, but up to now have usually freed them after payment of a ransom.

But gunmen who seized four foreign oil workers from the offshore EA oil platform run by Royal Dutch Shell more than two weeks ago are insisting on the release of regional militants and political leaders detained by the Nigerian government.

The same group is claiming responsibility for an attack four days later that destroyed Shell's Benisede oil pumping station in the delta swamps and left at least 12 people dead. The violence led Shell to evacuate more than 300 workers from other vulnerable facilities and close down about 10 percent of Nigeria's production.

'Guerrilla warfare'

And this week's attack on the offices of Italy's Agip oil company in the oil industry capital of Port Harcourt, in which nine policemen and one company employee were killed, bears all the hallmarks of the militants despite police calling it a robbery.

Armed men in military fatigues rode in speedboats to the riverside premises of Agip and opened fire on policemen guarding the main building. Police commissioner Samuel Adetuyi said the men took the equivalent of US $30,000 from an office before retreating into the maze of creeks that makes up the region.

Adetuyi described the assailants as robbers. But analysts see a new phase of violence emerging in a region that has seen nearly two decades of unrest.

This is not just another instalment in the delta violence we're used to,・said Pius Waritimi, a rights activist based in Port Harcourt.

We're entering another phase; this is guerrilla warfare.

The militant group claiming the recent kidnappings and attacks - the Movement for the Emancipation of the Niger Delta (MEND) - has displayed considerable military capability, repeatedly catching Nigerian security forces unawares.

MEND militants evaded navy troops guarding Shell's EA platform located six miles offshore in the shallow Atlantic waters adjoining the delta to invade a supply boat and seize four men.

The hostages are US citizen Patrick Landry, the boat's captain; his two ship engineers - Harry Ebanks from Honduras and Nilko Michev from Bulgaria; and Nigel Watson-Clark, a retired British paratrooper working as a security expert.

MEND's dawn attack on Benisede began with rocket attacks on the quarters housing soldiers stationed to guard the facility, followed by more blasts from explosives, Shell and military officials said. The Nigerian army said eight militants were killed in that attack and four soldiers confirmed dead, with 11 still missing and presumed dead.

Two major pipeline attacks since December claimed by the group have targeted Shell-operated trunk pipelines that carry crude oil produced in the delta swamps to its export terminals, in line with militants・vow to cripple exports.

Militants say locals deprived as oil flows

One prominent militia leader protesters want freed is Moujahid Dokubo-Asari, who led an armed uprising of ethnic Ijaw militants in 2004 to back demands for local control of oil resources in the Niger Delta.

Dokubo-Asari's demand has resonance among the ethnic minorities of the oil region, who feel deprived of oil wealth by an alliance of foreign oil companies and successive governments dominated by members from Nigeria's dominant ethnic groups.

Dokubo-Asari's threat to target oil companies last year helped drive global oil prices beyond the $50 mark for the first time. But his Niger Delta People's Volunteer Force (NDPVF) called off the threat after their leader met with President Olusegun Obasanjo and agreed to a truce. The group subsequently agreed to surrender its arms for cash.

But Dokubo-Asari, who remained a strident critic of the Nigerian government, was arrested in September and charged with treason after he declared in a newspaper interview he would fight for the disintegration of the country, Africa's most populous with more than 126 million people.

MEND is also calling for the release of Diepreye Alamieyeseigha, the former governor of Bayelsa state (Nigeria's only wholly Ijaw state), who is being held on corruption charges. Arrested in Britain on money laundering charges in September, Alamieyeseigha jumped bail in November and returned to his governorship in Nigeria.

Alamieyeseigha was arrested three weeks later by the police after his state's legislature impeached him as governor.

MEND insists both men are being persecuted by Obasanjo more for opposing his alleged plan to extend his rule and for their support of local control of oil revenue, than for any crimes they are alleged to have committed.

We don't want any money. We only want Dokubo-Asari and Alamieyeseigha released,・a man who gave his name as Brutus Ebipadei and described himself as MEND's leader, told IRIN by telephone. They're the only ones who can negotiate the release of the hostages.

Ebipadei added: we want the Nigerian state to leave our oil for us, and we have started our fight to achieve it.・He allowed the reporter to speak to two of the hostages, whom Shell confirmed as being among the company's kidnapped employees.

MEND does not claim any direct links with Dokubo-Asari's NDPVF apart from demanding his release. During a court appearance for his treason trial last week Dokubo-Asari said he did not know the group but expressed support for their action.

A Shell-sponsored security study completed in late 2003 showed a pattern of weapons influx into the delta fed by an illegal trade in crude oil and used in widespread violence claiming an average of 1,000 lives every year. The study predicted that violence may force Shell to quit onshore oil production in Nigeria by 2008.

Nigeria estimates that up to 10 percent of its oil production is sometimes lost through criminal gangs that siphon crude oil from pipelines for sale to tankers waiting offshore. Militant leader Dokubo-Asari has acknowledged in interviews that a major source of militia weaponry has been the illegal trade in crude oil.

While Obasanjo has remained restrained with regard to the hostage-taking - appealing to the militants not to do anything that could result in the loss of lives・- residents in the Niger Delta are beginning to flee for fear of military reprisals against local militia.

Similar standoffs in the past give citizens cause to worry. In November 1999, months after taking office as elected president after more than 15 years of military rule, Obasanjo sent troops after a group of armed militants that had killed 12 policemen. Government troops levelled the town of Odi where the killings had taken place and killed more than 1,000 people, according to human rights groups.

Almost everyone in my town has fled,・said Enitowari Inengi, a resident of Ozobo, a fishing community near Shell's Benisede facility. Everyone one is afraid the military will do to us what they did at Odi.・

But even getting at the militants poses a huge challenge for authorities as the delta environment - a region of more than 70,000 square kilometres criss-crossed by thousands of rivers and creeks - is impossible to police. Militants have used their mastery of the terrain as their main strength, taking refuge in the labyrinth of creeks from where they attack targets at will.

In a recent e-mail statement MEND said: we want to prove that the oil on our soil cannot be taken without our consent.

[ENDS]