Nigeria's anti-corruption agency arrests three former state governors for allegedly embezzling funds amounting to $674m (£436m).
The Economic and Financial Crimes Commission (EFCC) said the former governors of Ogun, Oyo and Nasarawa states faced a series of charges.
They are likely to appear in court in the next few days.
Correspondents say the EFCC has made high-profile arrests before but has found hard to make the charges stick.
'Abused state contracts'
Former Ogun state governor Olugbenga Daniel, Adebayo Alao-Akala of Oyo state and Aliyu Akwe Doma of Nasarawa state were arrested Thursday, EFCC spokesman Femi Babafemi said.
During their time in office, the men are alleged to have abused state contracts and diverted government money for their personal use.
Mr Babafemi said Mr Daniel is accused of defrauding the state of $387m. He said Mr Alao-Akala and Mr Doma each face $167m and $120m fraud allegations. All three men are members of the ruling party.
The BBC's Jonah Fisher in Lagos says the EFCC has arrested high-profile figures before, but has so far been less successful in making the charges stick.
Nigeria's justice system is painfully slow and ill-equipped to deal with complex financial cases, our correspondent says.