An Australian filmmaker has been sentenced by a Cambodian court to six years in prison on charges of spying for an unnamed country.
James Ricketson, 69, was arrested in June 2017 while flying a camera drone over an opposition rally.
Mr Ricketson denies the charges and his lawyer said he would appeal against the verdict.
His arrest comes amid a wider crackdown on dissent by the increasingly authoritarian government in Phnom Penh.
He has visited Cambodia frequently over the last 20 years and been a firm critic of Prime Minister Hun Sen.
Local pro-government media had labelled the filmmaker as a spy acting to promote revolution, but Mr Ricketson expressed only disbelief at the charge.
"Which country was I conducting espionage for?" he said in court after the verdict was announced, Reuters news agency reports.
"The Phnom Penh Municipal Court has decided to convict James Ricketson and sentences him to six years in prison for espionage and collecting information that is harmful to the nation between December 2010 and June 2017," Judge Seng Leang said.
During trial, the prosecution argued that Ricketson's work had damaged Cambodia's reputation on the world stage.
The prosecution's main argument relied on several emails in which he expressed sympathy for opposition groups.
In one email, he urged Australia's government to withdraw an invitation for Hun Sen in 2016.
His family has expressed dismay over the verdict stating: "James is not a spy. James loves Cambodia and the Cambodian people. He is a filmmaker and a humanitarian".
The filmmaker's lawyer told media that if the verdict is upheld, the Australian government should take diplomatic action.
The ruling comes as observers increasingly accuse Cambodia's government of authoritarian rule to suppress dissent.
The opposition Cambodia National Rescue Party (CNRP) behind the rally Mr Ricketson was filming has since been banned, leaving the government without any serious political opponent.
In this year's general election, Hun Sen's ruling party claimed a landslide victory, but it was a poll that was widely criticised for its failure to allow serious opposition.
Hun Sen, a former soldier in the Khmer Rouge who later opposed them, has presided over a sustained period of rapid economic growth.
But he has long been accused of using the courts and security forces to crush dissent and intimidate critics.