Cambodians are voting in an election that longtime leader Hun Sen is all but guaranteed to win as he looks to secure his legacy by handing the reins to his eldest son.
The 70-year-old former Khmer Rouge cadre has ruled since 1985 and faces no real contest in Sunday's vote, with opposition parties banned, challenger candidates forced to flee and freedom of expression stifled.
His Cambodian People's Party [CPP] is likely to retain all 125 seats in the lower house, prolonging his grip on power and paving the way for a dynastic succession.
The only serious opposition party was disqualified on a technicality in the runup to the polls and it will be a surprise if any of the 17 other small, poorly funded parties win seats.
Hun Sen cast his ballot in the capital Phnom Penh shortly after polling stations opened at 7:00 am [0000 GMT], according to the AFP news agency.
More than 9.7 million people are registered to vote in the seventh election since the United Nations first sponsored polls in 1993 after years of conflict — including the genocidal Khmer Rouge — left the country devastated.
Over the last 30 years what hopes the international community might have had for a vibrant multi-party democracy in Cambodia have been flattened by the juggernaut of Hun Sen's rule.
The veteran PM has begun to look to the future, saying he would hand over to his son, four-star general Hun Manet — possibly even in the coming weeks.
The 45-year-old scion led the final CPP rally in Phnom Penh ahead of polling day, telling a raucous crowd on Friday that it was "victory day" for the country.
Critics would disagree, and rights groups have condemned the election.
On the eve of voting, a 17-strong coalition — including the Asian Network for Free Elections [ANFREL] and the International Federation for Human Rights [FIDH] — characterised the polls as being of "profound concern".
"The upcoming electoral exercise indicates a notable absence of transparency, fairness, and inclusivity in the electoral process," the coalition said in a statement issued Saturday.
'I cannot evaluate'
In the days ahead of the polls, capital Phnom Penh was blanketed by huge posters of Hun Sen.
But many are now looking to Hun Manet, educated in the United States and Britain, wondering if a change in leadership might bring change to the country.
"For me, I want to see his work first then I can evaluate," one 73-year-old Cambodian told AFP.
"For now, I cannot evaluate anything at the moment," he added, declining to give his name.
Polls are due to close at 3:00 pm [local time], with early results expected within hours.