PHNOM PENH: A court in Cambodia jailed 11 opposition party members on Tuesday for insurrection after an anti-government protest turned violent a year ago, a verdict that could rock a fragile truce between the country’s rival political forces.

The 11 Cambodia National Rescue Party (CNRP) members received jail terms ranging from seven to 20 years for forcibly trying to reopen the country’s only designated protest venue, “Freedom Park”, defence lawyer Sorn Sudalen told Reuters.

The park was temporarily shut as outrage against the ruling Cambodia People’s Party (CPP) grew among activists and trade unions in the wake of a disputed 2013 election, rattling the administration of long-serving Prime Minister Hun Sen.

Chaos erupted during the rally, as security forces fired tear gas and charged CNRP supporters with batons.

Naly Pilorge, director of Cambodian rights group Licadho, described Tuesday’s court proceedings as a “show trial”.

“We are shocked,” she said. “This is another clear example of how the executive is using courts to threaten political activists.”

The CNRP activists were bailed as part of a peace agreement struck last year between the CPP and CNRP that led to the opposition ending its parliamentary boycott, but there have been signs of tension resurfacing.

Political experts have been sceptical about how lasting the “new culture of dialogue” would be, given the long and bitter history between heavyweights in the two parties.

CNRP, a reincarnation of a formerly impotent opposition, stunned the CPP in the 2013 election by winning votes from urban middle classes, disgruntled textiles workers and farmers angered by land grabs.

The 2018 election will be closely watched as former Khmer Rouge soldier Hun Sen seeks to extend a three-decade grip on power that critics say has been reinforced by the influence he wields over Cambodia’s judiciary, bureaucracy and military.