Scores of people, some carrying mourning flowers, gathered outside the Guangzhou offices of the Southern Weekly, a popular liberal paper which had an article urging greater protection of rights censored.
One man in a wheelchair held a banner reading: "Support the Southern Weekly, resist censorship, give back my freedom of speech."
Some demonstrators wore masks depicting the British revolutionary figure Guy Fawkes, adopted as an anarchist symbol internationally after being popularised in the film V for Vendetta which was recently broadcast on state television.
Police stood by allowing the rally to proceed, but as it dispersed for the day, a lone woman demonstrator stood outside the building, holding a white rose and raising one hand, making a victory sign with her fingers.
The second day of rare public protests pushing for greater rights in China came after bloggers and celebrities – some with millions of followers – voiced support online for freedom of the press.
Yao Chen, an actress who has 32-million followers, posted the paper's logo on China's Twitter-like Weibo service and quoted Russian dissident Alexsandr Solzhenitsyn: "One word of truth shall outweigh the whole world."
Southern Weekly used the same quote in its 2006 new year message.
Fellow actor Chen Kun, who has 27-million followers, replied: "I am not that deep, and don't play with words, I support the friends at Southern Weekly."
The popular blogger Han Han, named by Time magazine as one of the world's 100 most influential people in 2010, lamented the pressure that journalists faced.
"I hope we can give it some small strength and accompany it to keep it going," he wrote, referring to the Southern Weekly.
The row erupted after censors on Thursday blocked the paper's 2013 new year message calling for the realisation of a "dream of constitutionalism in China" and replaced it with an article in praise of the Communist Party, according to journalists.
Chinese media outlets are subject to directives from official propaganda departments, which often suppress news seen as negative by the ruling Communist party, but some publications take a more critical stance.
Avoiding a backlash
The dispute comes after the party's new leadership, headed by president-in-waiting Xi Jinping, took over at a congress in November, raising expectations of a more open style of governance.
The authorities seemed to be approaching the row cautiously to avoid a backlash that might trigger more protests, said Doug Young, a journalism professor at Fudan University in Shanghai.
"The government is treading really, really carefully in this incident because they have to make sure that it doesn't get out of control, say if they come across as acting too heavy-handed and start arresting people or trying to fire people," he said.
In a commentary the People's Daily, the Party's official mouthpiece, said propaganda chiefs needed to adapt to the "rhythm of the era" to ensure their effectiveness, and abandon "stiff preaching that is unchanging and patronising".
Analysts said the dispute was the latest instance of years of mounting tension between a heavily controlling government and a public increasingly assertive of its rights.
"It's part of the intensifying battle in the last decade," said Kerry Brown, director of the China Studies Centre at the University of Sydney. "You cannot just shut them up. This is not going to go away."
Unwavering basic principle
The US-based website China Digital Times posted what it called a message from propaganda authorities telling media outlets not to refer to the issue.
"Party control of the media is an unwavering basic principle" and "external hostile forces are involved in the development of the situation," it quoted it as saying.
The international media freedom group Reporters Without Borders praised the protestors' "show of courage" and called for the original article to be published.
But a commentary in the English-language Global Times, which is close to the ruling party, on Tuesday said authorities would not allow radical changes in media policy.
"The country is unlikely to have the 'absolutely free media' that is dreamed of by those activists," it said. "The Southern Weekly issue will not be concluded with a surprise ending." – AFP