By AP News Sep 26, 2013 6:48PM UTC

PHNOM PENH, Cambodia (AP) — Two Cambodian men wrongly convicted for the 2004 murder of a prominent opposition activist walked free on Thursday, one day after the country’s Supreme Court ordered their release.

The court’s decision to drop all charges came amid renewed calls to free the men, whom leading international rights groups have called “scapegoats” in the murder of Chea Vichea and one of many examples of the country’s corrupt judicial system.

Sok Sam Oeun, left, and Born Samnang appear in front of journalists at a Phnom Penh police station in 2004. They were freed on Thrusday after almost 10 years in jail after being wrongly convicted of Monday. Pic: AP.

Chea Vichea was the leader of Cambodian’s largest labor union, the Free Trade Union of Workers, and an outspoken critic of government corruption and human rights abuses.

He was gunned down in broad daylight on Jan. 22, 2004, at a roadside newsstand in the Phnom Penh after having received numerous death threats for his work as a labor organizer.

Within a week, two men — Born Samnang and Sok Sam Oeun — were arrested.

“We are very happy with this result, but this should not be the end,” Cambodia’s leading human rights groups said in a joint statement Wednesday. “It should be the opportunity to properly look into one of the most tragic deaths in Cambodia’s recent history.”

The investigation that followed the pair’s arrest nearly a decade ago sparked local and international outcry, as did the trial. None of the prosecution witnesses appeared, providing only written testimonies that could not be challenged in court. Several of those present for the defense were rejected.

In 2005, the men were convicted and sentenced to 20 years in prison, which was just the start of a roller coaster-like legal battle that lasted nearly a decade.

In 2008, the Supreme Court ordered a new investigation and retrial and the two men were released on bail from 2009-2012 but promptly jailed again when the Appeals Court upheld the original verdict and returned them to prison.

In total, they spent more than five years in prison.

The men had requested a re-hearing before the Supreme Court, which occurred Wednesday. The judges cited a lack of credible evidence as the reason for dropping the charges, the rights groups said in their joint statement.

New York-based Human Rights Watch welcomed the decision. The group’s Asia director, Brad Adams, said Thursday that the pair’s release was “a tribute to the persistence of Cambodian activists who sought to right a terrible wrong.”

“Inexplicably, the court denied the men the right to seek compensation for their judicial mistreatment,” Adams said. “All these years the government has taken no action to bring the real killers of Chea Vichea to justice.”

The hearing came amid an ongoing political crisis in Cambodia over July elections that the opposition says it lost because of cheating by Prime Minister Hun Sen’s ruling party.

Human Rights Watch called the case a test of whether the ruling party’s promised reforms “will actually take place, or whether the courts will continue to be a political tool of Prime Minister Hun Sen.”