
Police said they had evidence Arisman provoked protesters into grabbing and detaining Prime Minister Abhisit Vejjajiva. This charge was not related to the break-in at the summit venue in Pattaya, although Arisman was also seen there.
"It's a different offence,'' Suporn said.
The suspect would be held at the Border Patrol Police's first region headquarters in Pathum Thani, which police use for interrogating protesters, he said.
Taxi drivers and thousands of followers of the Democratic Alliance Against Dictatorship rallied in front of the Criminal Court, demanding Arisman's release, causing heavy traffic congestion on Ratchadaphisek Road.
They had learned he would be kept in custody there while police sought court approval for his detention.
Pheu Thai MP Karun Hosakul went to the court to post bail for Arisman while 300 red shirts blocked traffic outside the police headquarters. The attempt to secure a bail for Arisman did not succeed because the court had closed.
Nattawut Saikua, a red-shirt leader, denied that another leader - Jatuporn Prompan - had also been arrested. He said Jatuporn was accompanying Arisman to the Naresuan military camp in Phetchaburi's Cha-am district, where Arisman was to have been transferred after appearing before the Criminal Court.
He said he was sitting in the helicopter with Arisman when they realised they were not heading towards Pathum Thani, as the police had said, but to Hua Hin. On the way, the helicopter set down for re-fuelling.
Jatuporn said Arisman was separated from him and officials told him they would open negotiations with him. Then he found out Arisman was tied up and taken back to the helicopter, which left immediately without Jatuporn.