Four former Hong Kong lawmakers have been released after spending more than four years in prison for their conviction under a Beijing-imposed law that crushed a once-thriving pro-democracy movement.

John Clancey, right, an American lawyer who became the first foreigner arrested under Hong Kong's national security law, displays a book before appearing at a police station in Hong Kong Sunday, Feb. 28, 2021. (AP Photo/Vincent Yu)HONG KONG – Hong Kong police on Sunday detained 47 pro-democracy activists on charges of conspiracy to commit subversion under the city's national security law, in the largest mass charge against the semi-autonomous Chinese territory's opposition camp since the law came into effect last June. They allegedly violated the national security law that was imposed by Beijing for participating in unofficial election primaries for Hong Kong's legislature last year. Ad“Thank you to the people of Hong Kong for giving me the opportunity to contribute to society in the past 15 years,” Chu said in a post on his Facebook page. The security law criminalizes acts of subversion, secession, terrorism and collusion with foreign powers to intervene in Hong Kong's affairs.