13 February 2015, 07:35 GMT
The protesters, a motley assemblage of pro-democracy activists, handed out roses and copies of George Orwell's "1984" in an expression of public dissent in a nation still under strict martial law, AFP reports from the Thai capital.
The authorities responded by throwing up metal barriers to keep the protesters away from the city's downtown.
Some of the activists still managed to push through and several of them were detained by police.
Since Army Chief-turned-Prime Minister Prayuth Chan-Ocha declared martial law and seized power military authorities have banned political gatherings, censored the media, arrested and detained opponents.
