When Hong Kong’s richest tycoons declared their support for the city’s national security law in June, it wasn’t what they said that stood out as much as how they said it.

One by one, the financial hub’s most prominent capitalists — from Li Ka-shing to Raymond Kwok — delivered their endorsements in a strikingly similar way: by giving interviews or statements to Hong Kong newspapers controlled by China’s Communist Party.

It was a notable shift from last year, when the tycoons used a variety of media to weigh in on pro-democracy demonstrations, and a sign of growing influence for a publishing empire that China has spent decades amassing in Hong Kong. As the Chinese government moves to snuff out the city’s protest movement, it’s now tapping this empire to promote its agenda and, according to critics including independent publishers and pro-democracy lawmakers, silence dissenting voices like never before.