The Demosistō party’s Joshua Wong has been detained at Bangkok’s Suvarnabhumi Airport, reportedly at the request of China.

See also: ‘Nothing can stop people thinking,’ says Demosistō’s Agnes Chow as Joshua Wong detained in Thailand

The 19-year-old activist, who was one of the leaders of the 2014 Occupy protests, was due to speak about democracy at Chulalongkorn University.

Demosistō condemned the move and quoted Netiwit Chotipatpaisal, a Thai student-activist Wong was due to meet, as saying that he had been detained at immigration.

“According to Chotipatpaisal, the Thai authorities have received a letter from the Chinese government earlier regarding Wong’s visit. His request to see Wong, who is still currently in custody, has also been declined.”

Author Jason Y. Ng told HKFP that the incident was troubling:

“Before Joshua left, I helped him map out his itinerary and told him that there’s a 70% chance that he would either be stopped from boarding his flight in Hong Kong or refused entry in [Bangkok]… Now that it actually happened, I can’t say it’s unexpected but it’s nonetheless disappointing and troubling,” he said.

Ng said Wong is expected to be put on the next Emirates flight back to Hong Kong, departing at 2pm.

Sophie Richardson, China Director of Human Rights Watch, tweeted: “Beijing says, “Jump!” Bangkok says, “How high?”

Hong Kong immigration say they have contacted the Chinese consulate in Thailand whilst NGO Amnesty International say they are monitoring the case.

Wong’s detention comes almost a year after Swedish-Hong Kong bookseller Gui Minhai went missing from Thailand, only to resurface in China having been detained by police. His daughter Angela Gui said on Twitter that the case was extremely concerning.

Also last October, Chinese journalist Li Xin attempted to seek political asylum in Thailand but vanished en route to Laos.