Police will pursue arrest warrants for at least two people over their alleged involvement in extortion attempts by a group led by political activist Srisuwan Janya.
Pol Maj Gen Jaroonkiat Pankaew, deputy commissioner of the Central Investigation Bureau, said investigators are expected to pursue warrants against at least two more individuals on Friday.
The CIB deputy chief declined to give details about the new suspects but said they are believed to have played a crucial role in the alleged extortion attempts.
Earlier, Pol Maj Gen Jaroonkiat said there were more suspects at a higher level and the gang was bigger than initially thought.
Mr Srisuwan was arrested Friday at his home in Pathum Thani for allegedly demanding 3 million baht from Natthakit Khongthip, director-general of the Rice Department.
Two alleged accomplices, Yoswaris Chuklom, also known as Jeng Dokjik, and Phimnattha Chiraphutthiphak, were also arrested. They were granted bail of 400,000 baht each.
Ms Yoswaris was a member of a civil servant working group appointed by Deputy Prime Minister and Energy Minister Pirapan Salirathavibhaga, while Ms Phimnattha is a former United Thai Nation Party election candidate.
Following the scandal, Mr Yoswaris was removed as an adviser to UTN MP Sanya Nilsupan who is the chairman of the House committee on courts, public independent agencies and prosecution.
