From shops, offices and schools, people spilled into the street on Thursday to voice their shock and anger and above all defiance of the government.
It comes as the Thailand government announced emergency measures banning gatherings of five or more and introduced a new curfew of 6pm to bring to an end protests that have last three months.
Discontent has been simmering since February when the leaders of an opposition party, popular among young people, were banned from politics.
Many protesters say the move against the Future Forward Party was politically motivated.
A pandemic lockdown, which sent Thailand's economy into freefall, exposed the chasm between the billionaire class and the poor.
And in June, prominent activist Wanchalearm Satsaksit, who had been living in self-exile in neighbouring Cambodia, disappeared.
Activists in Thailand lit up Twitter with their demands for answers.
The online campaign spilled offline mid-July and a wave of protests across the country began, with up to 30,000 turning out in mid-September for what was the largest gathering since 2014.
Protesters arrested after police threaten tough action
More than 20 protesters, including prominent leaders, were arrested on Thursday, after the government declared an emergency decree banning gatherings of more than four people.
The emergency decree gives police powers to arrest anyone suspected to be involved in the protests.
Police said they would arrest all protesters, though they did not explain how they would charge tens of thousands of people.
#Thailand | Tens of thousands of people, including high-school students, gathered in #Bangkok on Thursday, defying a ban announced as part of a crackdown on pro-democracy protests. https://t.co/N4DXYRkzID pic.twitter.com/D5uMq0KKKb— Atlantide (@Atlantide4world) October 15, 2020
The Royal Palace has declined all comment on the protesters or their demands.
Until Wednesday, the government had largely allowed demonstrations to happen while making no sign of meeting protesters' demands.
But that changed after an incident in which protesters jeered Queen Suthida's motorcade as she and the king were paying a rare visit from Europe, where they spend most of their time.
The government cited the risks to national security and the economy from protests and the danger of spreading coronavirus – with demonstrators converging in large groups and failing to social distance – as reasons for imposing emergency measures.
The demonstrations are scenes only seen before the coronavirus pandemic, however Thailand has been relatively successful in controlling the spread of the infection.
According to Johns Hopkins University data, Thailand has reported just 59 deaths and a total of about 3600 cases since the start of the pandemic.
The government reported 13 new cases on Thursday, and there are 143 active cases throughout the country.
with Reuters and AFP
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