The National Anti-Corruption Commission (NACC) has set up a panel of advisers to help in its probe into the Rolls Royce bribery scandal.
It's alleged that former ministers and executives of Thai Airways International (THAI) are connected to bribes paid out by the British engineering giant.
The NACC wanted experts, from both within and outside the organisation, to help take its investigation further, NACC secretary-general, Sansern Poljeak said yesterday.
An initial probe appear to back allegations that Thai politicians and high-ranking officials were involved, he said.
A former transport minister, a former deputy transport minister, THAI executives and a panel formulating a long-term investment plan for the national carrier are on the NACC's list of suspects, he said.
He was referring to people who occupied those positions between 2004 and 2005.
They are believed to have been involved in the purchase of aircraft engines for Boeing B777-200 ERs and Airbus A340-500/600s from Rolls Royce in a deal during that period, Mr Sansern said.
The NACC believes the suspects abused their power or committed dereliction of duty in the deal.
Mr Sansern said if the anti-graft agency finds evidence pointing to their alleged wrongdoing, it will question all involved, no matter who they are.
Rolls Royce earlier admitted to a British court it had bribed Thai state officials and THAI employees to secure trade deals between 1991 and 2005.
The scandal involves kickbacks totalling 1.28 billion baht.
The NACC is also investigating the alleged involvement of the national oil and gas conglomerate PTT Plc, and its subsidiary PTT Exploration and Production Plc, in the scandal.
They bought power generators and equipment from Rolls Royce between 2000 and 2013.
The government has also set up a multi-agency committee to look into the case.
The investigations have progressed slowly as Thai authorities are awaiting documents requested from the Britain's Serious Fraud Office.