The Myanmar suspect, Naw Kham, earlier admitted to the murder charges in a China court hearing. Naw Kham and five other suspects were charged with intentional homicide, kidnapping and hijacking which ended with the death of 13 Chinese crew members of two boats.
Gen Yuthasak said the nine Thai soldiers, if implicated, will have to attend hearing in the Chinese court but the defendant must pinpoint the alleged wrongdoings with evidence.
The nine members of a Thai military task force who were initially charged with involvement in the murder were later cleared of the implications. However, the Myanmar suspect reversed his earlier statement.
China's official news agency Xinhua said Naw Kham was suspected of involvement in drug smuggling in the Golden Triangle which borders Thailand, Myanmar and Laos. He was handed over to China in May.