The sister, Marilyn Tang Yin-lee, 63, was a member of disbanded Hong Kong Confederation of Trade Unions, which was established by Elizabeth Tang and her husband, Lee, in 1990.

And the lawyer Frederick Ho Chun-ki, 65, was the younger brother of former lawmaker Albert Ho Chun-yan, who was also the ex-leader of the defunct Hong Kong Alliance in Support of Patriotic Democratic Movements of China.

It is learned that the duo's arrest on Saturday was in connection with the case in which Elizabeth Tang was arrested last Thursday over an accusation of collusion with foreign forces.

According to the police, the two were arrested for taking items including mobile phones, laptops, and documents away from Elizabeth Tang’s residential flat before the police launched a search operation in it.

Marilyn Tang was released on bail and left the police headquarters early this morning with the company of her elder sister’s companion, Elizabeth Tang, who was released on bail for HK$200,000, two days after she was detained.

Marilyn Tang and Frederick Ho were required to report to a police station in mid April.

Elizabeth Tang and her husband Lee built up the defunct Confederation of Trade Unions in 1990, after which Lee served as the president and Tang was the chief executive. Lee was arrested for taking part in his leadership of a Tiananmen crackdown vigil group in 2019 and convicted of organizing and inciting others to join unauthorized assemblies.