The United States on Wednesday called on Laos to resolve the mystery of the disappearance three years ago of prominent social activist Sombath Somphone, saying his abduction sent a "chilling message" on human rights.
Sombath went missing in Vientiane, the capital of Laos, on December 15, 2012. A video previously released by authorities shows him being stopped at a police checkpoint and being led into a pickup truck.
"The United States remains deeply concerned over [Sombath's] fate and the chilling message his abduction sends to members of civil society and the people of Laos more broadly," the U.S. State Department said. "We are troubled by the fact that no progress has been made in locating Mr. Somphone and call on the Lao government to conduct a thorough and transparent investigation. The government should take measures to resolve this case immediately."
The U.S. statement came as President Barack Obama's senior diplomat for Asia, Assistant Secretary of State Daniel Russel, was due in Laos for talks before the Southeast Asian country takes up the chairmanship of the 10-nation Association of Southeast Asian Nations next year.
Washington is keen to encourage ASEAN unity in the face of China's increasingly assertive behavior in the Asia-Pacific region and is concerned about the influence Beijing has in Laos.
On Monday, Laurent Meillan of the U.N. Human Rights office said Laos had shown "no political will to solve" the mystery of the abduction of Sombath.
Human Rights Watch said Laos' human rights record had grown worse since Sombath's disappearance.
Some rights groups believe Sombath annoyed someone powerful within the government, although the government as a whole has not been blamed for his disappearance.
Laos has signed, but not ratified, a global convention that protects individuals from enforced disappearance.