ROME – Following the news of the arrest of Hong Kong’s retired cardinal, the Vatican’s spokesman said the Holy See is following the situation “with extreme attention.”

Hong Kong’s national security police detained Cardinal Joseph Zen, retired archbishop of Hong Kong, along with former opposition lawmaker Margaret Ng Ngoi-yee, singer Denise Ho Wan-sze, and scholar Hui Po-keung, the UK-based human rights group Hong Kong Watch said on Wednesday.

Soon after the news broke, Matteo Bruni, spokesman for the Vatican, said that “the Holy See has learned with concern the news of Cardinal Zen’s arrest and is following the development of the situation with extreme attention.”

The arrests were reportedly related to their roles as trustees of the 612 Humanitarian Relief Fund, which provided legal aid to people who took part in pro-democracy protests during 2019. The social revolt was quashed by security forces, the group said.

According to Hong Kong Watch, the fund closed in 2021.

“We condemn the arrests of these activists whose supposed crime was funding legal aid for pro-democracy protestors back in 2019,” said Benedict Rogers, who leads the U.K based Hong Kong Watch. “Today’s arrests signal beyond a doubt that Beijing intends to intensify its crackdown on basic rights and freedoms in Hong Kong.”

He also urged the international community to shine a light on this “brutal crackdown and call for the immediate release of these activists.”

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Under Hong Kong’s 2020 security law, Zen could be sent to mainland China for trial if charged. The law declared participating in or supporting the pro-democracy movement to be crimes of subversion and collusion with foreign organizations. As such, it allowed those charged to be extradited to China to face trial, and a punishment that ranges from a minimum of three years to a maximum of life imprisonment.

Scores of pro-democracy activists have been arrested under this sweeping law imposed on Hong Kong by Beijing in 2020, following pro-democracy demonstrations. According to the Associated Press, the city’s independent media have been gutted and its legislature reorganized to pack it with Beijing loyalists.

Zen, 90, has publicly supported the pro-democracy and independence protests that roiled the city for much of the past decade and came to a head in 2019 with unprecedented street marches and six months of sporadic street battles with authorities.

Shortly after the security law was implemented, Zen posted a video on Facebook saying, “If right and proper words were considered against their law, I will endure all the suing, trials and arrests. Numerous predecessors have endured similarly.”

The prelate was also a strong critic of the Vatican’s 2018 controversial accord with China regarding the appointment of bishops. The efforts for such an agreement began during the pontificate of Pope emeritus Benedict XVI, and was signed four years ago. In October the two sides are set to determine whether they will renew the agreement for another two years.

Zen argued that the agreement would “kill” the underground church in China, whose leaders refuse to register with the state-run Chinese Catholic Patriotic Association. Beijing has a history of arresting and jailing priests and bishops.

Several leading Kong Kong activists have fled to Taiwan, Britain or elsewhere in recent months, while thousands of others have chosen to leave the city, raising concerns about the economic future of the Asian financial center of 7.4 million people.

Wednesday’s arrests follow the selection on Sunday of Hong Kong’s new leader, John Lee, a hardline former security chief who ran unopposed in a process controlled by Beijing. Lee, like his predecessor Carrie Lam, is a Catholic.

The European Union and foreign ministers from several countries, including the United States, Canada, France, Germany, Italy, Japan, and the United Kingdom condemned the election as fundamentally undemocratic and a betrayal of the “one country, two systems” principle under which Hong Kong was supposed to retain its own political, legal and economic system for 50 years after the end of British colonial rule.

Follow Inés San Martín on Twitter: @inesanma