Police in Hong Kong on Tuesday arrested Tommy Yuen, a popular singer and pro-democracy campaigner.

Local media and rights groups reported that Hong Kong authorities have also blocked access in the city to a pro-democracy website operated from the U.K.

Yuen, a former member of the Canto-pop boy band E-kids, was arrested by national security police over the suspicion of sedition and money laundering. He has not been charged.

Senior superintendent Steve Li declined to name Yuen as the 41-year-old man was taken away by national security officers. But he said during a press briefing that the man was arrested for making comments in public and online on social media that were deemed carrying “seditious intent.” 

The singer’s seditious acts, said Li, included the performance of a song containing lyrics “Liberate Hong Kong, revolution of our times” — a widely used slogan during the 2019 pro-democracy protests — in an online concert in November last year. Li said during last July’s first trial of a national security case, the court had established that the slogan could incite people to support secession of Hong Kong from China. The man in the July case was given a nine-year prison term for using the slogan on a banner.

Police also accused Yuen of spreading comments online to incite citizens to break the law, incite hatred against Hong Kong’s judicial system and incite public hatred against the police.

The singer was also accused of contradicting the city government’s strategy against the pandemic, claiming that those taking COVID-19 jabs could die. For nearly two years, Hong Kong had managed very low levels of virus infection. But since last month the Omicron variant has caused thousands of new cases and exposed the city’s health system as unprepared for such a large surge.

Police added that the singer has allegedly been involved in a money laundering case, and said that they had also arrested a 20-year-old unemployed man in connection.

Meanwhile, Hong Kong Watch, a rights group based in the U.K., said on Tuesday in a statement that internet service providers PCCW, CMHK and HKBN have used DNS adjustments to block access within the territory to its website.

It was not the first time that Hong Kong authorities have cut access to politically-sensitive websites. Others including HKChronicles.com, Transitional Justice Commission and HK Charter 2021 have been banned in a similar way, Hong Kong Watch said. They have also tried to close overseas-based sites, with mixed results.

“If this is not just a technical malfunction, and Hongkongers will no longer be able to access our website because of the National Security Law, then this is a serious blow to internet freedom,” said Benedict Rogers, CEO of Hong Kong Watch.

“With the steady drip of website removals, there are fears that China could begin introducing its Great Internet Firewall into the city.”

That is a reference to mainland China’s highly developed system of restricting access to thousands of political and news related websites and pages, known colloquially as The Great Firewall of China. China also denies its residents access to most social media and search services operated by Google, Facebook and Twitter.

These remain currently available in Hong Kong, but authorities have forced the closure of locally-based media operations that do not adopt a pro-Beijing line and politically vocal. And pro-democracy Hong Kong celebrities have been largely silenced since the implementation of the National Security Law in late June 2020.

Singer Denise Ho was arrested by national security police in December over her alleged connection with independent online media Stand News, where Ho was previously a board member. The media outlet subsequently folded and she was released on bail. Actor and singer Anthony Wong Yiu-ming was charged with corruption for performing at an election rally, but the charge was later dismissed.