Polling has now ended in Thailand in a general election boycotted by the opposition and blighted by protests.
Yingluck Shinawatra shows her vote at a ballot box at a Bangkok polling station. Photo: AFP
Anti-government activists forced some polling stations in Bangkok and the south to close but a large majority elsewhere were said to be peaceful.
Prime Minister Yingluck Shinawatra called the vote to head off weeks of mass protests aimed at forcing her to resign.
The BBC reports her party is widely expected to win but legal challenges and a lack of a quorum of MPs may create a political limbo.
Ms Yingluck, who won the last election in 2011, voted soon after polls opened on Sunday near her Bangkok home.
Her opponents took to the streets in November after her government tried to pass an amnesty law that would potentially have allowed her brother, Thaksin, to return from exile.
Thaksin, a former prime minister who fled during a court case in 2008, is reviled by the protesters, who say he controls the government from abroad.
Security has been heavy throughout Thailand, with vast areas under a state of emergency because of the protests.
Security officials said about 130,000 personnel had been deployed across Thailand on Sunday, including 12,000 in Bangkok.
There has been little campaigning for the election and it was unclear how many Thais had turned out.
Voting in 13 of Bangkok's 33 constituencies, and in 37 of 56 constituencies in the south was disrupted.
Polling in the rural north and east, where Ms Yingluck's Pheu Thai party has overwhelming support, was largely unaffected.
"Today is an important day,'" Ms Yingluck said as she voted. "I would like to invite Thai people to come out and vote to uphold democracy."
However, disruption to candidate registration means that even if she wins, there will not be enough MPs in parliament for Ms Yingluck to have full power over government policy, and by-elections will be needed.
Thousands of anti-government protesters held a rally in Bangkok on Saturday. Photo: AFP
The opposition is also likely to mount legal challenges to the election.
Ms Yingluck's party is already facing a host of challenges in the courts aiming to disband it, as has happened with pro-Thaksin parties in the past.
The Democrat Party, which is allied to the protesters, has been unable to win a majority in parliament for more than two decades.
Many of its members want the government to be replaced by an unelected "people's council" that would oversee wide reform of the political system.
Trouble broke out in Bangkok on Saturday in a violent clash between pro- and anti-government groups.
A gun battle erupted in the Lak Si constituency as anti-government protesters blockaded a building storing ballot papers.
At least seven people were wounded.
