The Office of the Attorney-General on Wednesday arraigned nine former key members of the Democrat Party on multiple charges relating to the anti-Yingluck Shinawatra government protests in Bangkok in 2013-14.
Deputy attorney-general Prayut Phetkhun said indictments were approved for Suthep Thaugsuban, 69, Sathit Wongnongtoei, 57, Chumpol Julasai, 48, Phutthipong Punnakanta, 50, Issara Somchai, 72, Withaya Kaeoparadai, 63, Thaworn Senniam, 71, Natthapol Teepasuwan, 52, and Akanat Promphan, 32.
They were leaders of the People's Democratic Reform Committee (PDRC) that organised the protests that culminated in the extended "Bangkok shutdown", with the occupation of many government of buildings throughout the capital.
The nine were charged with insurrection, illegal assembly and obstructing an election, among others. Mr Suthep and Mr Chumpol were also charged with terrorism.
Insurrection is punishable by death.
All nine accused showed up at the Office of the Attorney-General to hear the indictment decision on Thursday. They were then taken to the Criminal Court for arraignment and later released on conditional bail of 600,000 baht each with orders not to leave the country.
The Department of Special Investigation compiled and took the case to public prosecutors. It involved 57 accused people. Of these, 34 sought a delay in appearing to hear the indictment decision on Wednesday. Some of the accused were arraigned earlier.
Few PDRC supporters showed up on Wednesday.
The PDRC started its protests in November 2013 after the Pheu Thai Party-led government proposed a bill viewed as attempting to end legal action against former prime minister Thaksin Shinawatra.
The then-government invoked special law to ban the protests. Former prime minister Yingluck Shinawatra dissolved the House of Representatives in December 2013.
In January 2014 huge crowds of demonstrators blocked Bangkok's main streets, determined to "shut down" the government. Protesters in Bangkok and the South, the political strongholds of the Democrat Party, also prevented advance voting for the general election.
In May that year the caretaker Pheu Thai government was toppled by the coup d'etat led by Gen Prayut Chan-o-cha, the present prime minister.