PHNOM PENH -- Self-exiled Cambodian opposition leader Sam Rainsy, who has promised to lead a revolt against his country's government, said he was barred from boarding a Paris-to-Bangkok flight Thursday, while Cambodia's prime minister threatened that his adversary's supporters at home would "suffer."
After four years abroad, Rainsy vowed to return to the Southeast Asian country on Saturday with other leaders of his now-banned Cambodia National Rescue Party, intending to lead an uprising that ends Hun Sen's three-decade rule.
Rainsy had posted a photo of a Thai Airways International flight reservation on Facebook, indicating he would depart Paris-Charles De Gaulle airport at 12:30 p.m. Thursday and arrive in Bangkok at 6 a.m. Friday.
But Thai Prime Minister Prayuth Chan-ocha had said Wednesday that Rainsy would be denied entry in Thailand on his planned transit to Cambodia.
Having failed to board the flight, Rainsy told reporters near the airport's check-in counter that he believed his trip was blocked because Hun Sen had pressured Cambodia's neighboring countries.
"They said they have received from very high up the instruction not to allow me to board," Rainsy said, in footage shared on Twitter.
In Phnom Penh earlier on Thursday, Hun Sen had challenged his longtime adversary to fly directly to the country instead. Amid a crackdown on opposition supporters in Cambodia, the leader also issued a threat to Rainsy's supporters still inside the country.
"Those who are outside the fence are OK because they sleep soundly, but those inside the fence die," Hun Sen said.
Questions also emerged about whether the opposition leader held a valid ticket. An employee of the Thai flag carrier told The Associated Press that Rainsy did not have a booking for the Thursday flight, which was full.
The employee said a ticket in Rainsy's name was booked for Saturday. Indeed, the Thai Airways site showed a round-trip ticket from Paris to Bangkok on Nov. 9-15 under his name.
Addressing his supporters on Facebook after leaving the airport, Rainsy insisted he would buy a ticket with a different carrier. He claimed his so-far-thwarted trip could still be deemed a "success" because it showed Hun Sen was "scared."
After weeks of vowing to return to Cambodia and spark an uprising, opposition leaders now find their plans seemingly blocked by the country's neighbors in the Association of Southeast Asian Nations.
Mu Sochua, another senior figure in the Cambodia National Rescue Party, was detained by Malaysian immigration officials after arriving at Kuala Lumpur International Airport from Indonesia late Wednesday, reported Reuters. She was released and allowed into the country late on Thursday evening, according to a post on her Facebook page. Malaysia on Monday also detained two CNRP youth members attempting to fly to Thailand.
Cambodia sent arrest warrants for Rainsy to all 10 members of the Southeast Asian bloc in September.
By the letter of an ASEAN agreement, its members are not obligated to carry out the warrants. The treaty on mutual legal assistance in criminal matters states it does not apply to arrest or detention with a view to extradition, or the enforcement of criminal judgments imposed by the party requesting assistance. It also has provisions allowing countries to reject requests for assistance if the alleged crime is political in nature.
Prayuth was quoted by the Bangkok Post as saying that "according to our commitment to ASEAN, we will not interfere in each other's internal affairs, and we will not allow an anti-government person to use Thailand for activism."
In addition to sharing a copy of a plane ticket on Facebook, Rainsy posted a letter addressed to Prayuth requesting safe passage.
Following Prayuth's comments, Rainsy indicated that he might change his travel plans, telling Reuters that if an arrangement could not be made with Thailand he would "find some other ways."
"If I cannot go to Bangkok, I will board another plane for Kuala Lumpur, Jakarta or Singapore -- wherever I can go and where I can gather people to go with me," he said.
Also a French citizen, Rainsy has been living in Paris since 2015 after fleeing Cambodia to avoid prison time linked to a defamation suit. That case, and several subsequent convictions, are widely seen as politically motivated.
Rainsy told the Nikkei Asian Review last month that he expected at least one million people would rally to meet him should be return to the country.
But the difficulties of crossing through Thailand, where they hoped to mobilize Cambodian migrant workers, were far from unexpected. For example, Thai authorities last month prevented Sochua from entering the country.
Rainsy has the support of human rights advocates. In a statement on Wednesday, Teddy Baguilat, a board member for ASEAN Parliamentarians for Human Rights, called Thailand's decision to block Rainsy on political grounds "outrageous."
"Prime Minister Prayuth said he made the decision according to his commitment to ASEAN, but committing to ASEAN should mean championing democracy rather than supporting repressive regimes," said Baguilat, a former Philippine member of parliament. "It is time that ASEAN countries realize that it is more sustainable and in its own interest to promote democracy and human rights within the bloc rather than give free rein to unpredictable and reckless despotic leaders."
Rainsy, who has reneged on previous promises to return, has remained emphatic that he would re-enter Cambodia, despite the explicit threat of arrest.
However, even some from his own party are unconvinced. Kem Monovithya, daughter of CNRP co-founder Kem Sokha -- who has been under house arrest since 2017 -- called Rainsy's most recent promise a "PR stunt" in an interview with local outlet Voice of Democracy.
The Cambodian government accused Kem Sokha of involvement in a U.S.-backed coup plot and, months later, moved to dissolve the CNRP, paving the way for Hun Sen's ruling Cambodian People's Party to win every seat in the 2018 national election.
Since Rainsy announced his intention to return, the government has intensified its crackdown on dissent. Calling the plan a coup, it has arrested almost 50 people and has broadcast footage of seemingly forced confessions on television.
The pressure campaign has also extended abroad. The country's aviation authority reportedly warned air carriers they could face prosecution for ferrying members of the CNRP to Cambodia.
Cambodia is also continuing a show of military force to thwart the group's return. Troops, deployed to areas near the Thai border, have held drills with live ammunition and conducted formation marches through small provincial cities, with footage of the exercises aired on local television.
Meanwhile, Cambodia's ambassador to Indonesia crashed an event in Jakarta this week where Sochua was speaking and attempted, unsuccessfully, to have it shut down. The ambassador later released a statement calling on Indonesian authorities to arrest Sochua.
Phil Robertson, deputy director of Human Rights Watch's Asia division, said the government's response was a "frenzied" attempt to protect their "bogus narrative" that exercising democratic rights was somehow a coup.
"The one thing that Hun Sen lacks is democratic legitimacy, and so is changing the subject to national security and impugning the motives of opposition political leaders trying to exercise their rights to return home," he said.