The court scheduled the first hearing in the trial of Anont Phanrat, Winyu Rattanawannee and Anantasak Srisawas for October 16.

The three suspects have been in jail pending trial since their arrests in June. No one showed up to request bail for them yesterday.

In addition to premeditated murder, the three men also face charges of illegal possession of guns and ammunition and unauthorised carrying of arms in a public place.

Anont and Winyu initially confessed their guilt during the police investigation into Kobkul's murder. She was shot dead in her pickup truck on May 27. Her driver and a police officer assigned to protect her were injured in the attack.

Another suspect - Sa-ngad Phumpheng - committed suicide on May 31 and left a note claiming sole responsibility for the murder. However, public prosecutors decided to file charges against the other suspects.

A source said public prosecutors had not yet brought action against caretaker Senator Napinthorn Srisan-pang, alleged to be the mastermind behind Kobkul's murder, because more investigation was needed to prove the allegation.

Napinthorn has maintained his innocence and said he had no business or political conflict with Kobkul. However, the senator was implicated because one of the gunmen admitted to shooting Kobkul to repay Anantasak - a member of Muang Ratchaburi Municipality and the manager of Sri Muang Market, which is owned by Napinthorn.

Kobkul was about to open a fresh market not far from the Sri Muang Market, when she was killed.

Public prosecutors said they would announce their decision on Napinthorn on October 2.