HONG KONG (Reuters) - Scores of people were injured in Hong Kong during a chaotic weekend of anti-government protests that left one man in a critical condition, authorities said on Monday, and China called for a tougher stance to end months of unrest.

Twelve police officers were also injured during the weekend clashes, with more than 300 people ranging from 14 to 54 years of age arrested between Friday and Sunday, police said.

Chinese state media called on Monday for a tougher line against the protesters, who vandalized the local offices of state-run Xinhua news agency and other buildings, saying the violence damaged the city’s rule of law.

More demonstrations are planned this week to keep up pressure for demands that include an independent inquiry into police behavior and universal suffrage.

“We really see that people are very heavy-hearted. They don’t know what is going to happen tonight or maybe the next weekend. And there is a lot of worry,” pro-democracy lawmaker Charles Mok told Reuters.

More than 100 demonstrators, some wearing now-banned face masks, returned on Monday evening to a shopping center where a man had knifed several people on Sunday and bitten off a part of a politician’s ear before being beaten by protesters.

Those who gathered on Monday shouted at security guards and riot police who also briefly entered the complex in the eastern suburb of Taikoo Shing.

Police said they arrested three men involved in Sunday’s incident, including the suspected 48-year old assailant.

Riot police had stormed several shopping malls to disperse protests near families shopping on Sunday, after the worst violence in weeks on Saturday, when police fired tear gas, rubber bullets and a water cannon at crowds of black-clad demonstrators across the Chinese-ruled financial hub.

The city’s Hospital Authority told Reuters one person was in a critical condition, with two others serious, among a total of 30 injuries from Sunday alone.

Local media reported a life-threatening injury was sustained by a male student who fell from a height, but details of the incident remained unclear. The head of the boy’s university called on authorities to investigate the matter in a heated dialogue on campus with students on Monday evening.

While Hong Kong and its many businesses function normally during the week, many protests have sprung up spontaneously at weekends over the past five months.

Pro-democracy protesters are campaigning against what they see as Chinese meddling with the freedoms promised when the former British colony returned to Chinese rule in 1997. China denies doing so, and has blamed Western countries for stirring up trouble.

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‘V FOR VENDETTA’

Protesters have circulated plans on social media to mark Guy Fawkes Day on Tuesday around Hong Kong by putting on the white, smiling Guy Fawkes masks made popular by anti-establishment hackers, the film “V for Vendetta” and protesters globally.

Hong Kong’s embattled leader, Carrie Lam, banned face masks last month, invoking colonial-era emergency powers for the first time in more than 50 years, but protesters have largely ignored the ruling.

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The protests have divided Hong Kong and undermined its economy, with the police coming in for particular scrutiny.

Police canceled a planned press conference on Monday after several journalists from the public broadcaster and other local media turned up wearing helmets with signs that said “investigate police brutality” and “stop police lies”, and then refused to leave when asked by officials.

“We are not protesting...We are just using our clothes...to urge the police to change and stop the violence against the journalists,” said Ronson Chan of online news site The Stand News. Police said the journalists’ actions were “disrespectful” and “deprived the public of access to important information”.

Local media associations have condemned what they describe as a heavy-handed approach by the police toward journalists, while officers have said they are responding to an escalating cycle of violence in five months of protests.

Protesters smashed doors and windows and threw petrol bombs at Xinhua’s office on Saturday, and also set fire to metro stations and vandalized buildings, including an outlet of U.S. coffee chain Starbucks.

The city’s Foreign Correspondents’ Club expressed grave concern at the attack on Xinhua, stating that news organizations and journalists must be able to work in Hong Kong free from fear of attack and intimidation.

Mainland businesses, including banks or companies seen as supportive of China’s ruling Communist Party, have often been targeted by protesters.

Police said the protests have been a “man-made disaster” for the city with some 45 kilometers (28 miles) of roadside railings dismantled, and 145 rail stations vandalized.

“Rioters’ destructive acts serve no other purpose than to vent their anger at grievances real and imagined,” said Chief Superintendent Tse Chun-chung on Monday.

“Continuing this rampage is a lose-lose situation for Hong Kong. Everyone is a loser. Please don’t let violence take over our daily life. Everyone deserves freedom from fear.”