Phnom Penh - Cambodian opposition leader Kem Sokha was denied bail Tuesday, three weeks after a surprise arrest that rattled the fragile democracy.
Kem Sokha, main rival of strongman premier Hun Sen, was detained in the early hours of September 3, taken to a remote border prison and accused of treason and espionage for allegedly conspiring with foreign powers to overthrow the government.
Rights groups have blasted the "concocted" charges as nothing more than Hun Sen's latest legal manoeuvre to sideline opponents ahead of 2018 elections that will test his 32-year grip on power.
"The court decided to uphold the provisional detention warrant (of Kem Sokha)," Touch Tharith, a spokesman for the Court of Appeals, told AFP after the hearing.
Authorities refused to bring the opposition leader to the Phnom Penh court, prompting his legal team to boycott the proceedings which were closed to the public.
"We demanded Kem Sokha be present at the hearing, but the court decided to continue the proceedings so the lawyers boycotted the hearing and walked out," lawyer Sam Sokong told reporters.
In response, the Court of Appeals issued a statement saying it was uneccessary to bring the suspect to the courtroom as it was not an evidentiary hearing.
The court has not set a date for the trial or explained why it is necessary to detain Kem Sokha, 64, in the jail on the Vietnamese border.
On Tuesday dozens of supporters and opposition MPs, who were blocked from entering the courthouse by a column of police, rallied outside to call for their leader's release.
"It is hard to accept the treason charge. We feel it is very unjust to lock him in jail," said one supporter who requested anonymity.
Hun Sen has accused Washington of involvement in Kem Sokha's "secret plan" with foreign entities -- an allegation rejected as "absurd" by the US ambassador.
The wily premier has helped the impoverished emerge from the ashes of genocide and civil war during his three decades in power.
But he has faced a mounting challenge in recent years from Kem Sokha's Cambodia National Rescue Party (CNRP), buoyed by public frustration over corruption and rights abuses.
Ever since he nearly lost to the CNRP in 2013, rights groups say Hun Sen has smothered critics in the opposition, press and rights groups, often by using the courts as a cudgel.
Around a dozen opposition politicians have faced prosecutions since that poll, with Kem Sokha's predecessor Sam Rainsy forced to flee abroad to avoid a string of convictions which he says are politically motivated.
The CNRP nevertheless fared well in local elections earlier this year, shaking the confidence of Hun Sen's ruling party as it prepares for next year's national poll.//AFP