AKIPRESS.COM - A Hong Kong student activist who helped organize pro-democracy protests in the Chinese-ruled city in 2014 was detained on arrival in Thailand on Wednesday, immigration officials said, with his supporters accusing China of being behind the move, Reuters reported.

Bespectacled Joshua Wong, 19, was detained in Bangkok where he had been invited to speak at two universities about Hong Kong's "Umbrella Movement" street protests and on setting up his political party, Demosisto.

The protests in Hong Kong, the former British colony which returned to Chinese rule in 1997, presented Communist Party rulers in Beijing with one of their biggest political headaches in decades.

Wong was given 80 hours of community service by a Hong Kong court in August on a charge of unlawful assembly for taking part in a sit-in at the height of the protests in the Asian financial hub.

Thailand has been ruled by a military junta since a 2014 coup which was widely condemned by the West. Since then, the generals running Thailand have forged closer ties with Beijing.

Reuters was unable to reach the Thai government for comment on Wong's detention.

Wong said in a Facebook post on Tuesday night that he was concerned about his trip to Bangkok.

"We all know Thailand is not politically stable... It is also clear that it is close to the Chinese Communist Party," he said.

Wong was denied entry by Malaysia in May 2015 when he was due to give a series of talks on democracy in China.

Wong was invited by Chulalongkorn University's Faculty of Political Science to speak on the 40th anniversary of the bloody crackdown by the Thai army on student protesters. Organizers said he was detained at Bangkok's main airport on Wednesday morning.

Immigration officials confirmed to Reuters that Wong was prevented from entering Thailand and would be sent back to Hong Kong. Officials said they were under orders not to speak to the media about why Wong had been refused entry.

Human Rights Watch condemned Wong's detention.