Sombath Somphone, 60, is believed to be in state custody after police CCTV footage showed him being detained by police, his car driven away and then him being driven away separately in the company of two unidentified men. He has not been seen or heard from since the incident Saturday.
Sombath's Singaporean wife, Ng Shui Meng, in an appeal Wednesday to the Lao government, described the video footage that showed her husband's encounter late Saturday at a police post in the Lao capital Vientiane. What purports to be a copy of the video has now been posted on YouTube.
"It is now nearly four days since the disappearance of my husband and I have yet to hear anything of his whereabouts," she wrote, appealing to the government "to please investigate my husband's disappearance as soon as possible, release information of his whereabouts and ensure his safety."
Friends and colleagues of Sombath insist he has no known enemies.
Laos has an authoritarian government with little tolerance for dissent, but friends and associates said Sombath's work was neither directly political nor confrontational.
Sombath, 60, received the Ramon Magsaysay Award for Community Leadership, one of Asia's top civil honors, in 2005. He was director until five months ago of the Participatory Development Training Centre, which he founded in 1996 to promote education and leadership skills. He is also involved in a small enterprise selling village handicrafts.
The statement of the Lao Foreign Affairs Minsry spokesman, dated Wednesday and posted on the website of the state news agency KPL, acknowledges receiving appeals from Sombath's wife and a copy of the video.
It says it shows his car had been stopped for a routine check, and relates many of the same details described by Sombath's wife, of a man arriving on motorcycle, Sombath's jeep being driven away and a pickup truck with hazard lights arriving and later departing with at least two men "to an unknown destination." It said the men could not be identified and there was no sign of them being forced to get into the vehicle.
"Following the preliminary assessment of the incidence from the CCTV footage, the authorities concerned viewed that it may be possible Mr. Sombath has been kidnapped perhaps because of a personal conflict or a conflict in business," the statement said.
It added that "authorities concerned are currently and seriously investigating."
The latest U.S. State Department human rights report, for 2011, described Laos as an authoritarian state under one-party communist rule, and said that arbitrary arrests and detentions persisted in Laos despite laws prohibiting them. It also said "prison conditions were harsh and at times life-threatening, and corruption in the police and judiciary persisted."
The United States has voiced concern about Sombath's disappearance, with the State Department urging the Lao government to make every effort to locate the activist.
The statement from the Lao government spokesman failed to satisfy those worried about Sombath's safety.
"The Lao government needs to immediately reveal Sombath's location and release him," Brad Adams, Asia director at Human Rights Watch, said in statement issued Thursday.
"The Lao authorities should realize that the risk to their international reputation grows by leaps and bounds every day Sombath's whereabouts remain unknown," Adams warned.
Associated Press reporters Elisa Mala and Vee Intarakratug in Bangkok, and Matthew Pennington in Washington contributed to this report