A rights group says three Thai citizens who were accused of insulting the king have disappeared.
Thai Alliance for Human Rights claims there’s no sign of the trio after they were arrested in Vietnam.
However Prawit Wongsuwan, Thailand’s deputy prime minister, denies the activists were in Thai custody.
The incident comes months after two exiled critics of the monarchy were found dead.
Last week Thailand crowned its new king, Maha Vajiralongkorn, in an elaborate ceremony at the Grand Palace in Bangkok.

Four countries condemn Iranian attack on Ras Laffan in Qatar
Netanyahu says Iran no longer has uranium enrichment capacity
US objectives in Iran have not changed, says Hegseth
Trump vows no more attacks by Israel on Iran gas field
Trump hails Japanese leader, says Tokyo 'really stepping up to the plate' on Iran
