Lagos - A former head of Nigeria's state-run oil company is under investigation after almost $10m in cash was found at a property he owns.
The Economic and Financial Crimes Commission (EFCC), an anti-corruption agency, said it had seized $9.8m from a house belonging to Andrew Yakubu.
A further $92 700 was also found at the property in the northern city of Kaduna.
Images of the money - stacked in neat bundles and allegedly discovered in a safe - have featured prominently in the country's media for several days.
Nigeria is currently in recession and desperately in need of cash, having been hit hard by the slump in global oil prices since 2014 that has squeezed revenue and pushed up inflation.
EFCC spokesperson Wilson Uwujaren declined to say what would happen next. "We are still investigating the matter," he told AFP.
"At the end of our investigation we shall decide on our next line of action... Nothing is ruled out."
Yakubu has admitted that the money belongs to him but denied any wrongdoing, saying it was a gift from friends.
The EFCC said in a statement on Tuesday that a court in the northern city of Kano had ordered that the looted funds be forfeited to the government.
It said Yakubu was still in custody assisting with investigation.
Yakubu was group managing director of the Nigerian National Petroleum Corporation (NNPC) from 2012 to 2014, appointed by the president at the time, Goodluck Jonathan.
In early 2014 the governor of the Central Bank of Nigeria, Lamido Sanusi, outraged Jonathan and his government by claiming the NNPC had failed to remit $20bn in revenue.
The allegation cost Sanusi his job, officially on charges of "financial recklessness and misconduct", but his supporters saw the dismissal as politically motivated.
Jonathan and his oil minister, Diezani Alison-Madueke, repeatedly maintained that nothing like $20bn was missing.
Yakubu was dismissed in 2014. Critics said he did little to clean up the NNPC's reputation as one of the world's most opaque and corrupt state oil companies.
Since coming to power in May 2015, Jonathan's successor, Muhammadu Buhari, has vowed to reclaim what he says were "mind-boggling" sums of looted public cash.
One of his first moves as president was to overhaul the NNPC to introduce more transparency and efficiency.
Alison-Madueke has been caught up in the anti-corruption drive.
She is currently facing fraud charges in Nigeria and the prospect of having to forfeit $153m to the government on suspicions the sum was illegally obtained.
A court in Lagos was told on January 6 that the cash was allegedly siphoned from the NNPC and stashed in three bank accounts. Alison-Madueke, a former OPEC president has rejected the claim.
She has been on police bail in London since October 2015 after being arrested in connection with a British investigation into international corruption and money laundering.
Buhari's information minister Lai Mohammed announced Sunday that some $151m as well as eight billion naira ($26.3m) in stolen state funds had been recovered from just three people.
The $9.8m found at Yakubu's house was not part of the new recoveries, he said.
Debo Adeniran, from the Coalition Against Corrupt Leaders, a lobbying group, said those responsible should be made an example of and "not go scot-free".
"They should be put in special cells with their names and former offices boldly written on their prison uniforms so that the young ones can see those responsible for their problems," he said.
"There should be no sacred cows," he added.
Denja Yaqub, an assistant secretary with the Nigeria Labour Congress (NLC), said state coffers had for too long been treated as "an ATM for corrupt officials".
"Year after year, we continue to lose millions of dollars to a cabal who has held the country hostage because of their greed. This is why Nigeria is not making progress," he said.Read Fin24's top stories trending on Twitter: Fin24’s top stories