Fiji police have raided the offices of their own team investigating the 13-million US dollar agriculture ministry scam and sought help from the New Zealand Serious Fraud Office.
Fiji TV reports that members of the team were briefly detained for questioning and have been reassigned to other duties.
A new team has been appointed to complete the investigation which has been going on for three years with little result.
The police commissioner, Andrew Hughes, says one officer has himself been placed under investigation after it was alleged that he was compromised.
About 20 former and current cabinet ministers, prominent businessmen and public servants are likely to face charges.
The scam involved the distribution of farm implements, boats and engines bought at inflated prices from some businesses.
The interim government at the time said this was a farming assistance scheme but critics allege the money was used to buy votes in the 2001 general election.