The Criminal Court has denied a request for the release on bail of Chukiat "Justin" Saengwong, a member of the anti-government Ratsadon group arrested on a warrant approved by the Criminal Court.
Mr Chukiat, 30, was charged with multiple offences including lese majeste and inciting unrest under Sections 112 and 116 of the Criminal Code, and breaking the emergency decree over his involvement in a number of protests, the most recent on March 20.
Police allege that during Saturday's protest in front of the Supreme Court on Ratchadamnoen avenue in Bangkok's Phra Nakhon district, Mr Chukiat affixed a piece of paper on which were written offensive words to a portrait of His Majesty the King erected outside the premises. His action was recorded by a security camera, according to police.
After that some protesters allegedly set fire to the portrait, but others extinguished the flames. When the police asked the protesters to stop, they responded by throwing bottles and ping-pong bombs and firing projectiles from slingshots, according to police.
Mr Chukiat has denied the charges against him.
Chana Songkhram police on Tuesday sought approval via video conference with the Criminal Court to detain Mr Chukiat for 12 days, from March 23-April 3, pending completion of the investigation.
The court approved the police request.
An MP applied for Mr Chukiat's release on bail, using his position, valued at 1.1 million baht, as security.
The court rejected the bail request, explaining that if released the suspect may commit similar offences again.