Xinhua reported that the so far nine people have pleaded guilty to charges related to Chen allegedly embezzling $3.15 million in public funds and accepting bribes of about $9 million in a land purchase deal.
Chen has been detained in a Taipei jail since Nov. 12. He was first indicted Dec. 12 for money laundering and bribery while in office.
Three relatives of Chen, including son Chen Chih-chung, daughter-in-law Huang Jui-ching and brother-in-law Wu Chin-mao, told a court on Jan. 21 that they had laundered money.
Chen's wife Wu is scheduled to appear in court Feb. 10, the news service reported.