Request Igbikis was used to hiding behind a mask. He knew a little about oil pipelines, too — how to blow them up.

“Vandalizing, killing people, kidnapping people,” said Igbikis, 28, describing his life as a former member of the Niger Delta Strike Force, one of the rebel groups whose attacks in the creeks of southern Nigeria crippled the country’s oil industry.

What he was not familiar with was how to build a pipeline, which is why he was standing in a dark warehouse with a protective mask on his head and a welding torch in his hand, sending a fountain of sparks into the air. Before long the two pieces of four-inch pipe in front of him were neatly joined together.

“I am learning,” he said, unsmiling but proud. “I want to be a somebody.”

This month, Igbikis and 39 fellow former militants will graduate from their nine-month welding course in Port Harcourt, the delta’s biggest city, joining thousands of other ex-rebels who have graduated from education or training projects in Nigeria and abroad. They are all beneficiaries of a $405 million-a-year amnesty program that has become an unlikely success story for Nigeria’s government.

When it was started by the late president Umaru Yar’Adua in June 2009, the rebels’ raids on oil installations and personnel had halved oil production from more than 2 million barrels a day to as low as 800,000 a day in January 2009, according to the government’s figures. Few local activists believed the amnesty policy would work.

But within a little more than a year, more than 26,000 “armed agitators” had handed over their weapons in exchange for a $400 monthly payment and a promise of training. The attacks lessened and then stopped. Today oil output is between 2.4 million and 2.6 million barrels a day, the government says.

Although concerns remain about the cost of the amnesty, the long-term stability of the delta and the massive increase in oil theft or “bunkering” that has accompanied the drop in violence, many early critics of the program admit they were mistaken.

“I thought the amnesty was poorly planned, but I’ve had to eat humble pie,” said Inemo Samiama, executive director the Stakeholder Democracy Network, a civil society group. “Militant activities have practically ceased and normal life has returned.”

Keeping the rebel leaders happy was crucial to the program’s success. It helped that President Goodluck Jonathan, who played an important role in negotiations with the militants while he was vice president, was from the delta region. After initially fearing persecution, militant bosses such as Government Ekpumopolo, known as Tompolo, were comfortably housed in the capital, Abuja, and then controversially taking part in lucrative oil-related contracts.

For foot soldiers such as Igbikis, who said he was driven to militancy by joblessness and a sense of injustice, the amnesty terms were also generous. The $400-a-month stipend is nearly four times the minimum wage of local government workers. Together with the promise of training, it was enough to encourage most militants — and many nonmilitants, some allege — to renounce violence and join demobilization camps.

The government says that about 11,500 of those granted amnesty have been placed in formal education or given training since 2009. Nearly half of those took courses abroad, mainly learning skills such as welding, electrical installations, mechanics, marine diving and entrepreneurship. An additional 600 nonmilitants were awarded scholarships to overseas universities as part of the program.

But the program’s success is generating its own problems. Although it is now closed, thousands of people are still clamoring to join, including former militants who initially refused to sign up, fearing stigmatization. Growing resentment among unemployed young delta residents who did not take up arms is another problem.

“There was always a risk of the amnesty being seen to celebrate violence,” said Lawrence Pepple, technical adviser on reintegration for the Niger Delta Amnesty Program. “But we also have to give these former militants opportunities.”

Paying and educating the former militants is expensive, costing $405 million in 2012 alone and well over $1 billion since the program started. While that represents less than three days’ revenue from the increased oil production, it has nonetheless drawn criticism from politicians outside the delta, who say that the cost of appeasing and pacifying the region is too great. In addition, there is the suspected involvement of former militants in bunkering, which saw up to 400,000 million barrels a day stolen in March, suggesting that the resulting loss to the treasury and oil companies may exceed $1 billion a month.

Detractors also say the program has done little to address the underlying issues that caused the militancy. Despite its oil riches, the delta remains poor, underdeveloped and polluted.

Pepple acknowledges the continued challenges but said the amnesty program was never supposed to be “a panacea for all the problems. . . . Our mandate was the cessation of hostilities, and it has achieved that.”

Pepple said that the end date for payments to militants would depend on the “threat and needs of the region” but that it was unlikely to extend past 2015. That means new jobs and opportunities will have to be created to keep the former militants as well as other jobless youths satisfied.

At present that is not happening, which could have serious consequences. Belema Papamie, an adviser to the president from the Ijaw Youth Council, an influential body representing the delta’s largest ethnic group, said the various militant groups held back some of their weapons when accepting amnesty and may have acquired more.

“You can traumatize a man by training him and then not giving him a chance at a job,” Papamie said.

— Financial Times