They called on the post-coup government to free the student activist, whose real name is Jatupat Boonpatararaksa, and other so-called political prisoners.

Pai has been in custody since authorities arrested him for sharing a BBC news report deemed to be insulting to the monarchy.

The event took place close to the Grand Hyatt Erawan Hotel, where the government and the Stock Exchange of Thailand hosted an investment forum as part of a government attempt to woo foreign investments for the flagship Eastern Economic Corridor project.

Also present were Pai’s father, Viboon, and fellow-activist Sirawit Sereethiwat, who is better known as “Sergeant New”. A member of the National Human Rights Commission, Angkhana Neelapaijit, went to observe the event.

One student from Thammasat University said she wanted foreigners to understand Thailand’s political situation where there is no freedom of speech under the junta regime and the justice system is biased against ordinary people.