Voters in Thailand headed to the polls on Sunday in a referendum on a new junta-backed constitution that would pave the way for a general election in 2017 but require future elected governments to rule on the military's terms.
The ballot is the first major popularity test for the junta led by Prime Minister Prayuth Chan-ocha, who has suppressed political activity during the two years since he seized power in a 2014 coup.
Ahead of the referendum, polls suggested a small lead in favour of accepting the new constitution, but most voters were undecided. Preliminary results were expected at around 8.00 p.m. (1300 GMT).
The junta has said the constitution is designed to heal more than a decade of divisive politics in Thailand that has dented growth and left scores dead in civil unrest.
Critics, among them major political parties, say it aims to enshrine the military's political role for years to come.
Prayuth has said he will not resign if Thailand rejects the constitution and that an election will take place next year no matter what the outcome.
"I urge everyone to come out and vote... to decide on the future of the country," Prayuth told reporters after casting his vote at a polling station in northwest Bangkok early on Sunday.
Voting through mid-afternoon had been trouble-free, said Police Major General Piyaphan Pingmuang.
"There have been no incidents to indicate protests or any political movement today," he said. "Everything is smooth."
Around 200,000 police were deployed for the vote.
Of 21 cases of voters tearing ballot papers, some were deliberate and others accidental, said Boonyakiat Rakchartcharoen, deputy secretary-general of the Election Commission.
Two students were detained and charged on Saturday in the northeastern province of Chaiyaphum for handing out leaflets urging voters to vote against the referendum, police said.
The junta, formally known as the National Council for Peace and Order, forbid debate about the constitution and banned campaigning ahead of the vote.
The authorities have detained and charged dozens of people who have spoken against it, including politicians and student activists.
Amnesty International said on Friday the junta had created a chilling climate ahead of the vote through pervasive human rights violations.
The vote comes against the back-drop of concern about the health of King Bhumibol Adulyadej, 88. The military has for decades invoked its duty as defender of the deeply revered monarch to justify its interventions in politics.
DECADE OF TURMOIL
Critics say the charter is the military's attempt to make good on their failure to banish former Prime Minister Thaksin Shinawatra and his brand of populism from Thai politics after the coup that removed him in 2006.