Lt-General Montree Jamroon said yesterday that investigators had concluded the case report and were prepared to submit it to public prosecutors.

"Police worked hard on this case and were not disheartened by the fact that the suspects were influential figures. Since witnesses and the evidence are solid, we feel confident that we can punish the perpetrators," he said.

Three other suspects - a member of Muang Ratchaburi municipality and Sri Muang Market manager Anantasak Srisawas, Anont Phanrat and Winyu Rattanawannee - will face charges of conspiracy to murder, Montree said.