SINGAPORE (Reuters) - Singapore police are investigating a conference that Hong Kong democracy activist Joshua Wong addressed via Skype without a permit, police and one of the event’s organizers said on Friday.

Pro-democracy activist Joshua Wong shouts during a protest against what they call Beijing's interference over local politics and the rule of law a day before China's parliament is expected to announce their interpretation of the Basic Law in light of two pro independence lawmakers' oath-taking controversy in Hong Kong, China November 6, 2016. REUTERS/Tyrone Siu

Singapore issued new public speaking rules in October to clarify that foreign companies and individuals need a permit to sponsor or take part in certain events.

The government of the multi-ethnic island is sensitive about anything that it thinks could upset social harmony.

Wong, 20, who helped organize pro-democracy protests in Hong Kong in 2014, spoke to a “Civil Disobedience and Social Movements” conference in November, organized by a Singapore group called the Community Action Network.

Jolovan Wham of the network said although police advised him Wong needed a permit, he and other organizers went ahead anyway as they considered it a “simple discussion about the role of civil disobedience, social movements and civil society activism”.

“I didn’t’ think there was anything wrong with going ahead with the event. It’s a very harmless event, it was for a discussion, so I don’t understand why it should be restricted by these regulations,” Wham told Reuters.

Wham said police had questioned him for 45 minutes.

Police said they were investigating.

“Police confirm that a report has been lodged and investigations are ongoing,” said a police spokesperson who declined to be identified or give further details.

The Singapore foreign ministry did not respond to emailed requests for comment.

In October, Wong was denied entry and to Thailand where he was due to give talks on democracy, and sent back to Hong Kong. Thai Prime Minister Prayuth Chan-ocha said at the time his expulsion was a matter for China, not Thailand.

He was barred from entering Malaysia in 2015.

Wong’s difficulties in traveling in the region have raised concern among human rights groups about China’s influence.

In Hong Kong, Wong told Reuters that the Singapore police action constituted “political censorship” and he speculated that it was a result of Chinese pressure.

Chinese foreign ministry spokeswoman Hua Chunying said the Singapore government had taken the action and questions should be referred to it.

Ties between Singapore and China have been strained in recent months, particularly after the seizure of nine of the city-state’s troop carriers by Hong Kong customs on their way back from a military exercise in Taiwan.

Beijing disapproves of other counties maintaining military ties with self-ruled Taiwan, which Beijing considers a breakaway province.