National Rescue Party says it has won 46 percent of the vote while the ruling party garnered 51 percent.

The opposition in Cambodia claimed gains in local elections on Sunday that could shake Prime Minister Hun Sen’s longtime grip on power.

Hun Sen has repeatedly warned of civil war if his Cambodian People’s Party loses its majority in city and village councils to the main opposition party, which had made major gains in the general election four years ago when it claimed it was cheated out of outright victory. Sunday’s polls could have a major impact on Cambodia’s political landscape ahead of the 2018 general election.

Opposition party spokesman Yim Sovann said his Cambodia National Rescue Party won about 500 of the country’s 1,646 communes.

He said his party received 46 percent of the vote, up from 30 percent in the last local elections in 2012, while the ruling party got 51 percent, down from 62 percent in 2012.

“This is a huge victory for the Cambodia National Rescue Party,” Yim Sovann said at a news conference.

Official results will be announced June 25. The spokesman for the ruling party could not be reached for comment.

Sunday’s polls could have a major impact on Cambodia’s political landscape ahead of the 2018 general election [Reuters]

Hun Sen’s government has been accused of using violence against opponents, but in recent years has stalked its foes mostly in the courts.

Hun Sen on Friday appealed to political parties to accept the election outcome rather than make accusations of irregularities, saying courts can dissolve any party if it challenges the result of the vote.

Hun Sen and some of his top ministers have frequently used strong rhetoric leading up to the vote, warning of dire consequences should the opposition win, in what has been seen as an attempt to intimidate voters into supporting him.

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Transparency International, which deployed over a thousand election observers, said the elections “went smoothly with little to no violence or intimidation” although “unauthorised personnel” such as soldiers and commune chiefs were present at a quarter of polling stations, according to a statement released on Sunday night.

Cambodia’s ruling party can take some credit for bringing modest economic growth and stability to a country devastated by the communist Khmer Rouge’s regime in the 1970s. Hun Sen left the Khmer Rouge, which was responsible for the deaths of some 1.7 million people from starvation, disease and executions before it was toppled in 1979.