Crime Suppression Division chief Maj-General Winai Thongsong and Central Investigation Bureau chief Lt-General Montri Chamroon called a press conference yesterday to refute reports that a key suspect had implicated three more senior officers.

They said the investigators had not given out any information beyond what they had already divulged and was verifiable.

The key suspect, Sgt-Major Chakhrit Janthara, was reported to have named three majors-general as the plotters and two sergeants as having built the failed bomb in Lop Buri.

Montri rejected the report about the two sergeants. "We want to ask reporters not to instantly believe what they hear without considering the information. The news might confuse society and people might get the mistaken impression that police are making accusations without having evidence," he said.

Montri insisted there were only five suspects in the case and investigators were not considering arresting  anyone else at the moment.

Only four officers have been entrusted with updating the media on the case: Montri, Winai, Police Maj-General Assawin Kwanmuang, deputy commander of the CIB, and Maj-General Jate Mongkhol-hatthee, deputy commander of the Metropolitan Police Bureau.

General Pallop Pinmanee, who was sacked as deputy director of Internal Security Operations Command (Isoc) after the alleged assassination attempt, said Chakhrit's reference to a "General Por" as the mastermind was scripted by police and Chakhrit.

"That sergeant was only a driver. If I was the mastermind, there's no reason I would invite the driver to join in the plotting of such a big operation. Everyone in Isoc knows the sergeant doesn't look a particularly clever guy as you may think. Only mad people would include him in their project," Pallop said.

He denied he was the "big boss" of Isoc who Chakhrit claimed was the mastermind of the plot.

"The real boss of Isoc is Thaksin," he said.