Has Nigeria's Niger Delta managed to buy peace?

With two machine guns on board, the speed boat raced up and down the palm-fringed creek of Nigeria's oil-rich Niger Delta as several enthusiastic soldiers whooped with excitement.

Four larger well-armed vessels moved at a more sedate pace.

These Nigerian soldiers have good reason to be on high alert.

Gunmen recently ambushed a police boat killing 12 officers on board.

"Attacking law enforcement agents is like attacking the state," says the spokesman for the military's Joint Task Force, Lieutenant Colonel Onyema Nwachukwu.

"It is a dastardly blow… and we are not taking it lightly.

"I foresee a situation whereby those people, in order to gain recognition, may want to attack innocent civilians," he warned.

Following the attack, an email was sent to journalists stating that this ambush was the work of the Movement for the Emancipation of the Niger Delta (Mend).

"We remain resolute in our resumption of hostilities," the email said.

However the military and experienced Niger Delta watchers doubt that there is any link between the attack and Mend which was extremely active, kidnapping oil workers and severely disrupting oil production, prior to the 2009 amnesty deal.

"They are a set of criminals usurping the image of Mend to seek attention and perhaps remuneration," said Lieutenant Colonel Nwachukwu.

Expensive commitment

It is widely believed that the attack was the result of a disagreement over money amongst a group of former militants.

Critics say the root causes of conflict have not been addressed

By the look of things it will not be the last.

So far around 30,000 people have been granted amnesty by the Nigerian government.

In what is a very expensive commitment, each is supposed to receive 65,000 naira ($410, £265) per month.

Thousands have also been given training for jobs as diverse as pipe welding and learning to become a pilot.

The amnesty programme costs close to $500m a year, but that is small change compared to the extra oil money accrued since the peace deal was struck.

Production fell as low as 800,000 barrels a day when the militancy reached its peak.

Today officials say 2.4 million barrels are produced each day.

But critics say the root causes of conflict have not been addressed.

"We have seen that the federal government itself is only interested in the flow of oil," says Morris Alagoa of the campaign group Environmental Rights Action.

"Today we see that the former militant leaders are given so much money and inducements but in the communities people are still drinking from polluted waters, oil spills are not cleaned up and we don't have modern amenities - no good education facilities and no health care system," he said.

'Easy money'

In Yenagoa town, the capital of Bayelsa state, there are unmissable signs that some of the former militant leaders have become incredibly wealthy - sprawling gaudy mansions are well-known landmarks.

In his less ostentatious but nevertheless relatively luxurious home, I met Reuben Wilson who is guarded by six policemen.

"When I was in the creek… we see money easily," he said.

"We would call an oil company and say: 'If you don't give us this, we will blow up this facility', and they would send money to the camp.

"Anything we said, we need they would send to us."

The former self-styled "general" has his sights on getting extremely wealthy.

"An oil company came to my community recently and has already started drilling there. Now I am in charge of the security in that area," he said.

"By the grace of God, the oil company will give me a major contract to supply chemicals and equipment so in two or three years when you come back maybe you will see me in a big mansion."

'Ready for business'

In Yenagoa, a former soldier tells me he used to visit the militant camps in the Niger Delta to service their guns.

Mansions of former militants are now well-known landmarks in Yenagoa

He is from Azuzuama, the same community as the group that recently killed the policemen.

He does not want his identity revealed.

"Some of them, when they got the amnesty money, they later went and bought guns to carry out sea piracy activities," he said.

"The aim of re-arming is just for criminality… because they see that some of the ex-militant commanders have made so much money in life so they themselves are trying to get quick money," he told me, adding that former militants are also heavily involved in oil theft.

But whilst many of the ex-militant leaders are "living big", some of their former fighters are disgruntled.

"My money I receive is 40,000 naira instead of 65,000 and we don't like it. Let the government do something to favour us; if they don't, we can go back to our camps and do anything we like," said 29-year-old Solomon, who still hopes the amnesty commission will fund his education.

"The money has been cut by the bank manager and my 'Oga'," he said, referring to his former militant commander.

Despite Nigeria's oil wealth, 90% of its citizens live on less than $2 per day

In Yenagoa, there are signs that some of the oil money is being spent on development, as huge diggers build new roads.

"We must all as leaders make genuine efforts to create jobs and develop skills and prepare for the day after oil," says Seriake Dickson, the governor of Bayelsa state.

"This state is going to be a hub for tourism and a hub for agriculture and that's why we have also taken the issue of security very seriously. Bayelsa is ready for business."

The federal government is for now buying the peace.

But the underlying grievances remain here - the deep poverty, lack of development and pollution.

Until they are dealt with, it will be hard to stop people believing that crime pays in the Niger Delta which at times feels like a crooked casino.