The anti-graft agency, according to sources, is however poised to seek the assistance of the International Police Organisation (INTERPOL) to locate the runaway suspects.
The Nation also gathered authoritatively on Friday that the probe team had commenced a review of the contracts awarded to 27 firms to ascertain whether or not they were executed.
Detectives are also working round the clock to verify the actual amount withdrawn from the Excess Crude Account (ECA) for the National Integrated Power Project (NIPP).
Investigation by our correspondent revealed that efforts by EFCC detectives to locate some of the key suspects yielded no fruits as they have left Nigeria.
Those being sought for interrogation include some ex-officials of Niger Delta Power Holding Company (NDPHC/NIPP); Technical Committee and General Project Manager; a former MD of PHCN; ex-CEO of the Transmission Company of Nigeria; an ex-Head Transmission of the TCN and a businessman who was expected to supply nine gas turbines and auxiliaries at an alleged inflated cost of N185 billion ($1.55 billion).
Sources said the businessman keeps moving from one location to the other abroad apparently to evade arrest.
A source familiar with the investigation said: “So far, we are on course. But five key suspects have shifted base abroad to avoid being part of the ongoing investigation.
“We will engage INTERPOL and other international security agencies to track them down.
“We have sent letters of invitation to their known addresses but they have not responded.
“We were only told that they now stay abroad. We need them to come and explain the roles they played on the contracts and why certain jobs have not been completed.
“We have tried as much as possible not to detain most of the suspects being interrogated.
“Those who spent less than 24hours in custody were given administrative bail.”
“We have different figures of $16 billion, $13 billion, $10.4 billion and others. We need those in charge to explain. About three committees raised to review the projects in the past came up with different figures.
“In essence, we are extending this probe to the actual deductions from ECA.”
Meanwhile, a document showed on Friday that about 27 contracts were awarded for electricity generation and transmission.
Investigation confirmed that the EFCC was reviewing the activities of the 27 firms which benefitted from the electricity generation and transmission projects.
Another source added: “We have discovered that the defunct Power Holding Company (PHCN) separately received N22.297 billion and N162,467.57 billion; US$445.244.630.07 million; Euro 20,105,436.31 million; and £8,987,322 million for about 27 contracts on electricity generation and transmission.
“We are looking into whether or not the contracts were executed or not.
“Those who have completed their contracts have no cause to fear. But those who failed need to answer questions from our team on how things went wrong and where the cash is.”
But representatives of some of the companies were said to have claimed that some electricity generation and transmission projects have been completed.
A reliable source said: “Before inviting businessmen and companies, the EFCC should first of all call for files from relevant Ministries, Departments and Agencies (MDAs) for status report on some of these projects.
“Many of these projects have been completed. I only agree with you on a few defaulters who the EFCC should fish out. But we should not allow the probe to assume a blanket shape.”
The EFCC on Wednesday detained two top officials of the NDPHC, the company that supervised the execution of the $16 billion failed power projects.
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