Oct 29, 2009, 12:01 GMT
Four people may be charged for spreading rumours about Thailand's King Bhumibol's health.
The 81-year-old monarch has been hospitalised since mid-September with a lung infection.
Speculation about his prognosis triggered a slide in the country's stock market earlier this month and police are now looking into the source of the rumours.
It is an offence in Thailand to talk negatively about the monarchy, and the king's health is a sensitive topic in financial markets because he is seen as the sole unifying figure in a politically polarised country with a long history of coups and upheaval
Police Major General Panya Mamen, a deputy chief at the Central Investigation Bureau, said: "We're now gathering all the evidence and next week the police will be applying for warrants from the Criminal Court.
"These people will be charged with violating Article 14 of the 2007 Computer Offence Act covering the posting of false computerised information that causes harm to national security and the general public."
Thai Prime Minister Abhisit Vejjajiva added: "Police have information on this issue and if the evidence is clear, they would likely have to proceed with the case."
The Department of Special Investigations (DSI) is also conducting an inquiry into possible stock trading irregularities.
DSI Secretary-General Tarit Pengdit said: "We're trying to get to the bottom of it. We hope we can conclude this case within 30 days. We want it to be fast because investors and the public are interested."
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