The family of a self-exiled Thai democracy activist pleaded Sunday for his release, three days after he was allegedly abducted in neighbouring Cambodia.
Wanchalearm Satsaksit, a critic of the ex-general Prayut Chan-O-Cha's Thai government, was dragged into a black car on Thursday in Phnom Penh, Human Rights Watch claimed, citing witness and CCTV footage from security cameras.
But Cambodian police said they knew nothing of his alleged disappearance and that they were not going to open an investigation.
"Please release Wanchalearm. We will look forward to this with hope," his family said in a statement.
"We hope this enforced disappearance will be the last time."
Wanchalearm is wanted in Thailand for running an acerbic anti-government Facebook page.
He had allegedly breached the Computer Crimes Act and Article 116 in the Thai penal code, which criminalises writings that create "chaos", said National Police spokesman Krissana Pattanacharoen.
But "although (Wanchalearm) is wanted by Thai authorities, we have followed strict rules and regulations" in requesting information from other parties, he told AFP.
Krissana said Thai police had "no idea" about the dissident's whereabouts.
Since the May 2014 coup, Thailand has vowed to track down pro-democracy critics of the government, especially those accused of attacked the kingdom's unassailable monarchy.
At least eight prominent Thai activists who fled after the last coup to Laos, Cambodia and Vietnam have subsequently disappeared, according to HRW.
A few hours before his alleged disappearance, Wanchalearm had posted on his personal Facebook account, writing cryptically "Compromise Mode".
Since Friday, Thai social media users have expressed anger online, using the hashtag "Save Wanchalearm", which trended over the weekend on Twitter.
Prayut's government emerged from the 2019 elections, but remains a legacy of the coup five years earlier with a cabinet stacked with ex-generals and their military allies.
They have become increasingly unpopular, especially as the coronavirus rips through the Thai economy.
In an expletive-laden video posted on Facebook June 3 which ran up 12,000 views, Wanchalearm had hammered the government and the premier for his "failed administrative skills".
Cambodian police have ruled out a probe into the alleged disappearance of a self-exiled Thai democracy activist in Phnom Penh