The Criminal Court on Wednesday approved a police request to detain Thai Patriots Network leaders Chaiwat Sinsuwong and Somboon Thongburan for 12 days from Jan 19-30.
Mr Chaiwat and Mr Somboon were arrested by Crime Suppression Division police acting on court warrants at a restaurant on Tuesday on charges in connection with the seizure of Suvarnabhumi and Don Mueang airports by yellow-shirt People's Alliance for Democracy protesters in late 2008.
Mr Chaiwat faces nine charges, including terrorism, and Mr Somboon seven, including terrorism.
CSD police took the two to the Criminal Court on Wednesday morning, seeking permission to detain them for 12 days from Jan 19-30.
The two did not request release on bail, even though police said they would not oppose it, subject to conditions. They instead submitted a petition challenging the CSD's detention application, saying they had been falsely charged.
The court this afternoon approved the request for 12 days detention, and dismissed their petition.
Sophon Thitithampruek, chief of the Bangkok Remand Prison, said Mr Chaiwat and Mr Somboon would be detained separately from United Front for Democracy against Dictatorship (UDD) members, who also are detained at the prison, to avoid problems.
The two would be put in Zone 1 where no red-shirts are being detained.
Since the red-shirts are usually allowed visitors from 10am-11am, the visiting time for Mr Chaiwat and Mr Wiboon would be after 11am, Mr Sophon said.
They were arrested shortly after they led TPN supporters in a march from Government House to the Grand Palace and submit a petition to His Majesty the King.
The petition asked His Majesty the King to help the seven Thais being tried in Cambodia on illegal entry and other charges.
Six of the Thais have been freed on bail. The only one still behind bars is Veera Somkwamkid, a TPN coordinator.
Meanwhile, in another round of talks with Pol Maj-Gen Kreerin Inkaew, deputy chief of the Metropolitan Police Bureau, and Pol Maj-Gen Wichai Sangprapai, the Metropolitan Police Division 1 chief, core members of the Thai Patriots Network agreed to open two lanes of Phitsanulok road to traffic starting tomorrow between 6am-10am and 3pm-6pm.
The protesters earlier refused to yield to the police request.