Police said eight officers and at least one reporter were injured during the clashes, and 13 protesters were arrested.
Protest organizers called for the demonstration to end just after 6 p.m. but a stand-off between police and hundreds of protesters continued for several hours before officers dispersed the crowd just before the start of a 9 p.m. curfew in force in the Thai capital.
Police intervened with force after some protesters tried to dismantle barbed wire and metal barricades set up by the authorities to block roads from Democracy Monument to Government House where the Prime Minister works.
Deputy police spokesman Kissana Phathanacharoen said the protesters attacked police with “ping-pong bombs, sling shots and fire crackers”. He added that the police actions followed laws and regulations and fully complied with international standards in controlling crowds.
Street protests against the Prime Minister have been held in recent weeks by several groups, including Prayuth’s former political allies, as frustrations grow over the mounting coronavirus infections and the damage the pandemic has done to the economy.
Many protesters on Sunday carried mock body-bags to represent coronavirus deaths.
“The government has been poor at managing the situation and if we don’t do anything there will be no change,” protester Kanyaporn Veeratat, 34, told Reuters.
The protest marked one year since the first of a wave of large-scale street protests led by youth groups that attracted hundreds of thousands of people across the country.On Monday, Thailand reported 11,784 new Covid-19 cases — its fourth consecutive day of record infections — and 81 related deaths, bringing total fatalities to 3,422 with 415,170 total cases registered.
