Hong Kong, Aug 11 : The Hong Kong business tycoon Jimmy Lai has been arrested along with other pro-democracy and media figures, raising fears of a broad crackdown by China.
Lai's Apple Daily newspaper offices were raided on Monday over allegations of collusion with foreign forces, the BBC reported.
His case is the most high-profile arrest so far under a controversial security law imposed by China in June.
Lai has been a prominent pro-democracy voice and a supporter of protests that erupted last year.
In February the 71-year-old, who also holds UK citizenship, was charged with illegal assembly and intimidation. He was granted police bail.
Chinese state media outlet the Global Times on Monday described Lai as "riot supporter" and his publications as having been "instigating hatred, spreading rumours and smearing Hong Kong authorities and the mainland for years".
Scores of police were seen entering the offices Apple Daily and Lai was led through the offices in handcuffs. According to the Global Times, two of his sons as well as two senior executives of Next Digital, a media company founded by Lai, were also arrested.
Hong Kong police confirmed that they had arrested 10 people - nine men and one woman - aged between 23 and 72.
Reports said that police gathered hours later on Monday at the house of prominent pro-democracy activist Agnes Chow. Fellow activist Nathan Law wrote in a post on Twitter that Chow had been arrested.
"Agnes Chow is arrested under National Security Law and we are still acquiring information about the content of the arrests. Horrible day," he wrote.
And UK-based ITV News reported that Wilson Li, a freelance journalist who worked with the channel, had been arrested, also on suspicion of collusion with foreign powers. Another activist, Andy Li, was also arrested, ITV said in a statement.
The sweep of arrests has raised fears that China will use its newly implemented security law to undertake a broad crackdown on Hong Kong's pro-democracy activists and media figures.
Law said on Twitter that his "worst fears" were being realised, adding that the arrests represented the "end of freedom of press in Hong Kong".
"The national security law is quashing the freedom of our society, spreading politics of fear," he said.
Unnamed sources within Apple Daily are cited as saying the company was "arranging lawyers", seeing the situation as "straight harassment".
Steven Butler, Asia programme co-ordinator of the Committee to Protect Journalists, said the arrest "bears out the worst fears that Hong Kong's national security law would be used to suppress critical pro-democracy opinion and restrict press freedom".
"Jimmy Lai should be released at once and any charges dropped," he said.
Wang Dan, dissident and exiled student leader of the 1989 Tiananmen Square protests, said on social media that the arrest "was expected" but "very outrageous because his two sons were also arrested, which was obviously an attempt by the authorities to destroy Lai's will through family ties".
"I call on the international community to take immediate action." Hong Kong has had a high degree of autonomy since it was returned to Chinese rule in 1997, and its residents have had a far higher level of freedom of speech and media than people on the mainland.
But the law's key provisions include that crimes of secession, subversion, terrorism and collusion with foreign forces are punishable by a maximum sentence of life in prison.
It makes it easier to punish protesters, and reduces Hong Kong's autonomy.
The law also gives Beijing powers to shape life in the former British colony in a way it has never had before.
Critics say it effectively curtails protest and freedom of speech. China has said the new law will return stability to the territory after a year of unrest.
There have been two previous waves of arrests since the law was passed by Beijing on 30 June.
The first one saw several protesters arrested the next day, as they staged a demonstration.
On 30 July, four students and former pro-independence activists were arrested under the law.
Other activists, like Law, fled the city before the security law came into force.
Law is currently in the UK but media reports are suggesting that Chinese authorities are seeking the arrest of him and other activists in exile.