The Cambodian government issued an 18-minute propaganda film on Monday, insinuating that political dissidents Sam Serey, Sourn Serey Ratha and Sam Rainsy are “terrorists” working together to overthrow Hun Sen’s regime.

The video, titled The Movement Bringing Danger to the Country, opens with a picture of Serey, founder of the Khmer National Liberation Front, who was recently accused of plotting a bomb attack, and attempts to link him to both Rainsy and Serey Ratha.

However, despite repeated assertions over the years that the three are terrorists, no concrete evidence has ever substantiated the claims, prompting observers to suggest that the government was using “the ultimate political smear” to project legitimacy ahead of this year’s widely questioned elections.

“This peace is disturbed by some rebel groups working with foreigners to create a movement to cause turmoil again with the ambition to seize power,” reads the narrator. “Those dishonest attempts failed under the leadership of peace bringer Samdech [Hun Sen],” the narrator continues.

Hun Sen claimed he foiled Serey’s purported plot to bomb the capital’s Wat Phnom before the Khmer New Year, with the government later releasing a dossier seeking to link him to former Cambodia National Rescue Party leader Sam Rainsy and various other groups. The dossier accused Serey of working with Rainsy to raise an army in Norway, and claimed Serey’s former employer – documentary filmmaker Bradley Cox – was a CIA agent giving Serey instructions.

More than 20 of Serey’s supporters have been arrested over the years for their membership in the “terrorist” KNLF, most for participating in nonviolent protests. None have ever been found to be in possession of weapons.

Rainsy, meanwhile, has lived abroad since 2015 to avoid politically tinged charges, while CNRP co-founder Kem Sokha was arrested for treason in September. The party – the country’s second-largest – was subsequently forcibly dissolved over unsubstantiated accusations it was fomenting “revolution”. Since then, the government has vigorously promoted a narrative that the dissolution was necessary to protect “peace and stability”.

Monday’s video intersperses clips of Hun Sen and his wife dancing on stage during Khmer New Year with menacing displays of military equipment like tanks and BM-21 rocket launchers and admonitions to take “at any cost, all the official measures of the government in preventing or destroying the dishonest plan of the terrorist or rebel group”.

Both Serey and Rainsy have denied any association with each other. On Tuesday, Denmark-based Serey reiterated that he never planned to commit any violent acts.

“They themselves want to create event and fabricate the evidence to make deep political crisis. I am Khmer, I have a rights to express my opinion or run [a] political party,” he said in a message.

The propaganda video also sought to link the pair to Serey Ratha, former president of the Khmer Power Party and head of the Khmer People Power Movement, which has also been labelled a “terrorist” group despite a lack of evidence. The label was abruptly dropped in 2015, however, when he was pardoned and allowed to enter the political arena. But his political career proved short-lived after he was convicted of inciting soldiers to disobey orders following a Facebook post critical of senior military officers.

Serey, Rainsy and Serey Ratha have all been convicted of politically tinged crimes, although none have actually been charged under Cambodia’s anti-terrorism laws.

Cambodian political analyst Hang Vitou said the accusations of terrorism were an excuse for the government to “flex its muscle” before the election.

“It might be perceived by the people that only the government led by the CPP can defend the country,” he said.

Sidney Jones, director of the Institute for Policy Analysis of Conflict, said neither the CNRP nor KNLF were on her radar as a security threat.

“CNRP and KNLF have NEVER appeared as violent groups in any forum I’ve ever seen,” she said via email.

Phil Robertson, deputy director of Human Rights Watch’s Asia division, meanwhile, said that the accusation of terrorism was likely made with ulter-ior motives in mind.

Calling it the “ultimate political smear”, Robertson said Hun Sen used invented threats to pose as a “champion of Cambodian sovereignty”.

“Of course, the reality is exactly the opposite, since the only proponent of undermining democracy is Hun Sen himself, with his illegitimate national election in July and his laughable claims to care about the rule of law,” he said.

Ministry of Interior spokesman Khieu Sopheak said Monday’s video was released to inform the public and deter them from joining any insurrectionist movement.

“Any plan, if there is no participation from the people, will fail,” he said.

When asked why no arrests have been made in the latest purported bomb plot, despite claims that the Ministry is monitoring those involved, Sopheak said the police are working on the case confidentially and will act when ready.

“We won’t make waves in the water to panic the fish,” he said.