The Economic and Financial Crimes Commission (EFCC) has arrested two of the 77 Nigerians on FBI list.
The suspects, Chika Augustine and Godspower Nwachukwu, were arrested in Abuja.
The breakthrough was announced by the new Abuja Zonal Head, Mr Aminu Aliyu at a briefing.
He said $35,000 has been recovered from one of them (Chika Augustine).
According to the Commission Zonal Head, another suspect, who had long been on FBI radar, was picked up in November 2018, investigated and ready for trial.
Asked if the suspects on FBI list would be extradited, Mr Aliyu said that the decision was between the EFCC headquarters and FBI.
A 252-count federal grand jury indictment unsealed in August charged 77 Nigerian nationals with participating in a massive conspiracy to steal millions of dollars through a variety of fraud schemes and launder the funds through a Los Angeles-based money laundering network as uncovered by the FBI.