Hong Kong national security police on Thursday detained four people, including the brother of prominent activist Dennis Kwok, one of eight fugitives with bounties on their heads for allegedly breaching national security.
The city's national security department "took in two men and two women from various districts in Hong Kong and Kowloon for investigation," a police source told AFP.
Among the four was the elder brother of former democracy lawmaker Dennis Kwok, who is currently in the United States.
"(Kwok's elder brother) is now under investigation in the Western District police station," the source said.
Three others, "two women and a man", were taken in Tuesday by the national security department, authorities told AFP earlier Thursday.
AFP has requested comment from police on the most recent detentions.
The source confirmed the three detained Tuesday were the elder brother, sister-in-law and nephew of prominent unionist Mung Siu-tat, who is also among the eight wanted.
They were "suspected of assisting persons wanted by Police (for continuing to) commit acts and engage in activities that endanger national security," police told AFP in a statement.
"Investigation is underway and further operations, including arrest, may be made."
Mung's relatives were allowed to leave the police station the same day, said local newspaper Sing Tao Daily, citing unnamed sources.
The rash of detentions comes two weeks after authorities offered rewards of HK$1 million ($128,000) for information leading to the arrest of eight prominent democracy activists now based abroad, accusing them of subversion, foreign collusion and other crimes.
The bounties have incited an outcry from the United States, Britain, and Australia -- all countries where the eight are living.
Mung and Kwok's families were not the first to be targeted by the national security department -- last week, three family members of Nathan Law, another of the wanted activists, were also briefly taken in for questioning.
A longtime labour rights unionist, Mung is currently in Britain where he continues to advocate for those in Hong Kong targeted under the national security law, imposed after massive democracy protests kicked off in 2019.
"I don't believe they can silence us. I have made it clear that I will not stop my advocacy and activism," Mung told AFP earlier this week.
But he said the Hong Kong government's bounties would have "some rippling effects".
"They are not only mounting pressure on us but also making those who live in Hong Kong dare not to maintain contact with us," he said.
Police have arrested 260 people under the national security law so far, with 79 of them convicted or awaiting sentencing in Hong Kong.
