Hong Kong police have arrested six people from an independent news outlet for "conspiracy to publish seditious publications", BBC reports.
Both current and former staff members of Stand News were among those targeted.
More than 200 police officers were also sent to raid the publication's office, with search operations still underway.
Police said in a statement that they were authorised to "search and seize relevant journalistic materials".
The current and former chief editors of Stand News were among those arrested, as well as pop star turned democracy icon Denise Ho, who was a former board member.
She confirmed in a Facebook post that she had been arrested on the same charge, and had been taken to Western District Police Station.
Those arrested - three men and three women - are aged between 34 and 73 years old.
Footage posted on Stand News' Facebook page also showed multiple police officers at the door of deputy assignment director Ronson Chan early Wednesday morning.
Chan was not arrested but he was taken in for questioning by police.
The night before, Chan had hosted the annual dinner of the Hong Kong Journalists Association (HKJA), of which he is chairperson. In a speech, he referenced the closure of Apple Daily, saying that the incident had "shaken" Hong Kong.
He concluded by saying the city would "always need the truth and always need journalists .... no matter how difficult the road ahead is, the
will not fall down".
