Prayuth, a retired general and former commander of the Royal Thai Army, seized power when he led a military coup in 2014. He ran the country with absolute power as the autocratic leader of the junta, and over the years has transformed himself from a uniform-wearing general to a suit-clad politician. He was formally elected prime minister last June, beating the billionaire leader of the pro-democracy Future Forward Party, Thanathorn Juangroongruangkit. Authorities have since disqualified Thanathorn from parliament and have moved to ban his party outright, leading to the biggest protest in years last month as thousands took to the streets against the government. Demonstrators chanted, “Long live democracy, dictatorship get out.”

Sunday’s run could be an even larger demonstration still, with some 10,000 people already registered for the event. “We want to show the government the discontent that citizens have with the administration,” student activist Tanawat Wongchai, who is part of a network young organizers of the run, told Reuters.

Thailand has seen “unending repression of fundamental rights and freedoms” since the 2014 coup, according to advocacy group Human Rights Watch. The government’s latest moves against Thanathorn and his party, which came a surprise third in last spring’s election by attracting the support of millions of young voters, have only served to reinforce people’s grievances over the increasingly repressive political climate.

The government hasn’t made it easy for the protest organizers. A press conference to launch the event at the Foreign Correspondents’ Club of Thailand last month was cancelled under pressure from local police, according to a statement from the club. “The police explained that the title of the event was objectionable, and that they considered it likely to create what they called a ‘mob,’ ” the club said. Plans to move the presser to a hotel similarly fell through, again under pressure from authorities, according to Tanawat. Organizers finally managed to hold the conference at Thammasat University.

Elsewhere in Thailand, attempts by other organizers to hold spin-off running protests have been barred in at least three provinces, according to local media.

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