Bangkok: Millions of Thais on Sunday appeared to have voted in favour of a new constitution that will give extra powers to the country's military, which seized control of the government in a 2014 coup.
According to the country's Election Commission, with 91 per cent of the votes counted so far, 61 per cent have voted in favour, BBC reported.
Voting across 94,000 polling stations opened at 8 a.m., and closed at 4 p.m. The official results were expected by 9 p.m.
This is the second referendum after 2007. Around 50.5 million Thais of the total population of 65 million were eligible to vote this time, compared to 45 million eligible in the last referendum.
The 50 million eligible voters were asked to answer "yes" or "no" to the question: "Do you accept the draft constitution?"
They were also asked a supplementary question, whether or not the appointed senate should be allowed to join the lower house in selecting a prime minister, the BBC reported.
If a majority of voters say yes, the draft becomes the 20th constitution of Thailand, enhancing the military government's legitimacy in the run-up to an election which Prime Minister Prayuth Chan-o-cha, who led the 2014 coup, has promised will happen next year.
If the constitution does not pass, what will happen is uncertain, but the military government will remain in control.
Prayut and former Prime Ministers Yingluck Shinawatra and Abhisit Vejjajiva cast their votes earlier on Sunday, BBC added.
"Come out (to vote) because today is important for the future of the country," Prayut said after casting his ballot.
"This is your duty and this is part of democracy, of an internationally-recognised process," BBC quoted the premier as saying.
About 200,000 police officers were deployed to maintain order and there were no reports of protests.