The martial law allows them to be detained without charges for seven days.
They were brought to the Army Auditorium in Thewes at 8:30 am.
They included United Front of Democracy against Dictatorship chairman Jatuporn Prompan, Nuttawut Saikuar, Weng Tojirakarn, Virakarn Musigapong, Nisit Sinthuprai, Kwanchai Praiphana, Pracha Promnok, and Chaiya Sasomsup.
The Nation