Yuen is accused of posting hate speech to incite opposition to the government, the judicial system and the SAR's anti-epidemic measures. He also raised around HK$1 million online in the name of helping protesters but is suspected of pocketing the money, police said.

Senior police superintendent Steve Li Kwai-wah, of the police's national-security department, said yesterday that alongside the 41-year-old Yuen, a 20-year-old jobless man was arrested for money laundering.

Li added that the two men were relatives, with sources saying the younger suspect is Yuen's ex-wife's younger brother surnamed Wong.

Li said the singer started to post seditious content on social media in September. During an online concert in November, the singer performed a song with "liberate Hong Kong, revolution of our times" in the lyrics, he said.

"When he sang the song, he meant to provoke Hongkongers to seek change through illegal means." Li added that the singer also cursed judges and mocked police officers.

"After the fifth wave of the Covid-19 outbreak began, the singer began to smear the SAR's anti-epidemic measures, urging the public to boycott the vaccination program and other measures."

Li also noted that the singer appealed to the public to donate money to support protesters and raised around HK$1 million.

Most of the money was spent by Yuen personally, Li said, including HK$150,000 for entertainment and HK$270,000 for gambling.

Yuen, a former member of boyband E-kids, has supported the pro-democracy camp over the past few years. He participated in events including the 2019 Human Rights Day Rally, where he led the protest march.