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Nigerian whistleblower under investigation for alleged corruption

A Nigerian legislator who uncovered a $6.8 billion scam in state fuel subsidy payments has been suspended while police investigate claims he demanded a bribe from a fuel trader, in exchange for keeping him off the list.

Farouk Lawan's parliamentary probe blew the whistle on one of the biggest corruption scandals in Nigeria's history in April, revealing a web of collusion between oil ministry officials and fuel marketers to claim subsidy payments for billions of gallons of fuel that was never delivered.

But allegations that he demanded - and took some of - a $3 million bribe from one of Nigeria's richest oil tycoons Femi Otedola to scrub his name off the list have cast doubt on the whole report.

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"The house should suspend Farouk Lawan as the chairman of the ad-hoc committee on the monitoring of the utilization of the fuel subsidy pending the investigation of the bribery allegation against him," the resolution said.

Lawan was still being questioned by police on Friday and unavailable for comment.

The national press this week quoted Otedola as saying Lawan approached him for a bribe, some of which he paid but secretly filmed it so he could expose Lawan.

When voting on the report, parliament inexplicably voted to remove Zenon from the list of fuel companies abusing the subsidy - the report initially estimated that Zenon owed at least $1.4 million to the government for fraudulent subsidy payments.

The house also resolved on Friday to put Zenon back on the list in the report.

It is not clear if the allegation is a smear campaign, a frequent tactic in Nigerian politics.

Lawan had called for the board of the state oil firm to resign, including including its head, Oil Minister Diezani Alison-Madueke, and the firm's chief executive Austen Oniwon -- two of the most powerful people in Nigeria that few would dare take on.

Parliament's speaker Aminu Tambuwal defended the probe into fuel subsidy abuses.

"We reject in totality the insinuations that the allegation has eroded the integrity of the outcome of our investigation into the management of fuel subsidy," he said.

"We have not been compromised ... in our stand against corruption."

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