The Guardian reports:
Up to a thousand protesters gathered in the centre of Guangzhou shouting slogans, before police dispersed them peacefully. A witness said most were in their twenties, although some were middle-aged.
The controversy broke out when the local committee of the Chinese People's Political Consultative Conference – a political advisory body – urged authorities to ensure that Mandarin, which is spoken across the country, is used on Guangzhou TV's main shows. It said the move would promote unity and help tourists and athletes who will arrive in the city for the Asian Games this November.
Although the network has said it will continue to broadcast in both languages, residents fear that Cantonese is being squeezed out and could ultimately be dropped completely. They argue there are already plenty of Mandarin channels for people to watch and say that a decline in the use of the language will also erode the area's cultural heritage.
In a poll on the committee's own website, 80% of the 30,000 respondents said Guangzhou TV stations should broadcast in Cantonese.
The English edition of the official newspaper The Global Times described the row as a "culture war". It reported that the company spent 30m yuan (£3m) switching its business channel to Mandarin last year, only to see ratings drop.
See also an AFP story "Southern Chinese oppose ban on Cantonese TV" from July 7.
View pictures of the protest here via flickr and watch footage from YouTube: