A young Hong Kong activist who was among the first arrested under Beijing's new national security law was detained on Tuesday close to the US consulate, local media and activists reported.
Tony Chung, 19, was led away from a coffee shop opposite the consulate by unidentified men, the South China Morning Post reported, citing a staff reporter who witnessed events.
The Post, as well as HK01 and iCable News, cited investigation sources as saying Chung had been detained by Hong Kong police's new national security unit.
Student Localism, a pro-independence group that Chung was once associated with before the security law came in, posted on Facebook on Tuesday saying the teenager was "missing".
The group added two other former members were arrested by police on Tuesday.
A previously unknown group calling itself "Friends of Hong Kong" sent a statement to media on Tuesday morning saying its members had been trying to arrange for Chung to make an asylum application via the US consulate.
"Our plan was for him to enter the consulate office today," a member of the group, who asked not to be named, told AFP.
AFP was not able to independently verify the group's claim that it was helping Chung make an asylum application.
Its statement said members witnessed four men walk into the coffee shop opposite the consulate at 8:15 am and detain Chung.
Dashcam footage obtained by AFP from a car parked opposite the building at that time showed three men wearing surgical masks escorting another man in a dark t-shirt who appears to have his hands behind his back.
The Friends of Hong Kong member told AFP the clothes worn by the escorted man matched what Chung was wearing that morning.
Calls to Chung's phone went unanswered on Tuesday.
Hong Kong police and the US consulate did not respond to enquiries seeking information.
Anyone detained by Hong Kong police has to be presented in court within 48 hours.
- 'Inciting secession' -
Beijing's new security law also allows China's security agents to operate openly in Hong Kong, unbound by local laws.
No contact details for that unit -- which is based out of a recently requisitioned hotel -- has been made available to the media.
Beijing imposed its new security law on Hong Kong in June following last year's huge and often violent pro-democracy protests.
It targets four types of crime -- secession, subversion, terrorism and collusion.
Critics say its broad wording criminalises a wide array of political speech and views, including calling for independence or greater autonomy for Hong Kong.
Chung was the first public figure to be arrested under the law.
In July he and three others, including a 16-year-old, were arrested for allegedly "inciting secession" via social media posts.
He was later released on bail although he was banned from leaving Hong Kong while the investigation remains ongoing.
Student Localism says its Hong Kong chapter disbanded before the security law was enacted and that its activists are now based overseas.