MELBOURNE (Reuters) - An Australian filmmaker arrived in Sydney on Sunday after a pardon by Cambodia’s king released him from a six-year jail sentence for espionage that he received after flying a drone over an opposition rally.

James Ricketson, 69, was last month found guilty of spying and collecting information harmful to the nation following a trial that was criticized by rights activists.

His arrest in June 2017, after he flew the drone above a rally by the now-dissolved opposition Cambodia National Rescue Party (CNRP), came amid a wider crackdown on freedom of expression by the government of Prime Minister Hun Sen.

Ricketson, who spent more than a year behind bars, denied the charges and sought a pardon from King Norodom Sihamoni. On Friday, he was released from Phnom Penh’s Prey Sar prison.

Greeted by family and friends at Sydney airport, he told reporters he planned to return to Cambodia.

“I’ll be going back as soon as I can but I’ll need to recover obviously,” Ricketson said.

His family thanked the king for bringing their “nightmare” to an end. Australia’s foreign ministry also thanked Cambodia for the release of Ricketson, who has been visiting Cambodia for more than 20 years.

In a letter to Hun Sen last month, the filmmaker apologized for statements to media that were disrespectful to the long-serving prime minister.

In July, Hun Sen’s Cambodian People’s Party (CPP) claimed victory following a general election in which it was largely unopposed. Rights groups said the vote was neither free nor fair given the absence of a significant challenger to Hun Sen, who has ruled for 33 years.