An anti-coup group filed a lawsuit on Friday against Prime Minister Prayut Chan-o-cha and four others for overthrowing the elected government last year.
The case filed at the Criminal Court by 15 members of the Resistant Citizen group names five members of the National Council for Peace and Order (NCPO).
In addition to Gen Prayut, they are Adm Narong Pipatanasai, the navy commander at the time of the coup; ACM Prajin Juntong, then air force chief; Pol Gen Adul Saengsingkaew, the police commander at the time; and Gen Tanasak Patimaprakorn, who was then supreme commander.
Members of the Young People for Social Democracy Movement protest at the Oct 14 Memorial on Ratchadamnoen Avenue on Friday before being taken away by police.(Photo by Apichart Jinakul)
Pansak Srithep, a group member, said members filed the case on the grounds that they were damaged by the coup.
He said 44 members had planned to sign on as plaintiffs but the number was reduced due to pressure from authorities and their family members.
The court will decide on May 29 whether to accept the case, he added.
Police later took the group members to the Phahon Yothin station for questioning.
Soldiers also took 11 members of another group called the Young People for Social Democracy Movement, Thailand, to the Chana Songkhram police station after they defied a police order by holding a political forum at the Oct 14 Memorial on Ratchadamnoen Avenue.
About 30 soldiers sealed the venue but the members gathered on the pedestrian walkway to read out a statement and diaplay anti-coup banners.
Staging a political gathering of more than five people was cited as the reasion to detain them, but they were released without charges a few hours later.