Chinese state media was slow to pick up the story of the pro-democracy protests in Hong Kong, initially offering little coverage. On Thursday, however, state media took a dramatically harsher line, with the official People’s Daily newspaper calling the demonstrations illegal and warning that if they are to continue, the “consequences will be unimaginable.”

For those living on the Chinese mainland, it may be tough to hear another point of view. The University of Hong Kong China Media Project's Weiboscope tool has shown a remarkable spike in the number of posts censored on Chinese social networks recently.

Western TV channels like BBC and China are available in China, but the censorship can be even more stark: The screen simply goes blank when Hong Kong is about to be mentioned.

This video from journalist Prashant Rao gives a sense of what it looks like.

Others have reported similar events:

This isn't a new situation, of course.

In one recent episode of Anderson Cooper's "AC 360," the shows producers set up a camera showing how they were being broadcast in China: As a segment on Christian leaders in China began, the screen went blank straight away: