Nigeria bank chiefs quizzed in vote-rigging cash probe

Nigeria's central bank on Wednesday said it was investigating some banks in connection with slush funds allegedly set up by a former oil minister to rig last year's elections.

The Central Bank of Nigeria said it was "fully aware and indeed a part of the ongoing investigation of certain financial transactions in some banks by law enforcement authorities".

It was conducting its own "special examinations and investigations" into the claims, as well as who may be involved, vowing not to allow the banking system to be used for fraud.

The statement from the bank follows accusations last week against Diezani Alison-Madueke, who was former president Goodluck Jonathan's minister of petroleum resources until last year.

She has been accused of bribing electoral officials with $115 million (100 million euros) in oil money through banks to influence the vote in favour of Jonathan's Peoples Democratic Party (PDP).

Nigeria's anti-corruption agency, the Economic and Financial Crimes Commission, confirmed on Wednesday it has questioned the heads of Access Bank, Fidelity Bank and Sterling Bank.

Some officials from the Independent National Electoral Commission and local oil executives have also been quizzed, it added.

Jonathan lost the election in March 2015 to Muhammadu Buhari, who since becoming president in May last year has embarked on a wide-ranging drive against endemic corruption.

He has accused the PDP of leaving the treasury "virtually empty" and vowed to recover "mind-boggling" sums of money looted by government and public officials over decades.

Alison-Madueke, 55, has been dogged by a range of corruption claims throughout her career.

During her tenure, the former CBN governor Lamido Sanusi accused the state-run oil company of failing to remit $20 billion in revenue to the central bank. He was then removed from his post.

Last October Alison-Madueke was arrested in London, where she was undergoing breast cancer treatment, in relation to a probe into international corruption and money laundering.