Explainer: What to know about Hong Kong’s past Tiananmen commemorations and nat. security trial of vigil leaders

Hong Kong pro-democracy activists Chow Hang-tung and Lee Cheuk-yan are facing national security trials, with Chow arguing that the prosecution is a test of the law's legitimacy. This comes amid a backdrop of increasingly stringent national security laws introduced in Hong Kong. Historically, the city has been a place for commemorating the Tiananmen Square protests, but recent legal actions have cast a shadow over these gatherings and the freedom of expression they once symbolized, raising concerns about the erosion of democratic freedoms in the region.