Violence broke out across the New Territories of Hong Kong on the 24th straight weekend of anti-government protests, with police firing tear gas to break up rallies as activists blocked roads and damaged shopping malls.

Protesters vandalised a train station in the central new town of Sha Tin and smashed up a restaurant perceived as being pro-Beijing, just two weeks before planned district council elections, the lowest tier of voting in the Chinese-ruled city.

The rail station was closed in Sha Tin, amid scuffles between police and protesters, on a day of planned shopping mall protests throughout the territory.

Shopping districts across the harbour on the main island were quiet.

"Radical protesters have been gathering in multiple locations across the territories," police said in a statement.

"They have been loitering in several malls and vandalising shops and facilities therein, neglecting the safety of members of the public."

Protesters daubed graffiti on shop fronts in Kowloon Tong and "stormed" shops in Tsuen Wan, police said.

Police stand guard after entering the Citywalk shopping mall in Tsuen Wan 

Last weekend, anti-government protesters crowded into a shopping mall when a man slashed people with a knife and bit off part of a politician's ear.

The protesters are furious at what they see as police brutality and meddling by Beijing in the former British colony's freedoms, guaranteed by the "one country, two systems" formula in place since it returned to Chinese rule in 1997.

China denies interfering in Hong Kong and has blamed Western countries for stirring up trouble.

Thousands of people gathered last night at a vigil for "martyrs", after a student died in hospital this week following a high fall.

Though the vigil ended peacefully, many attendees called for revenge after the student's death from injuries sustained during a protest.

Seven pro-democracy city politicians have been detained or face arrest and are due to appear in court tomorrow on charges of obstructing a May meeting of the local assembly, police and said.

"We believe that the government together with the police, as well as the pro-establishment camp, they are trying to escalate the anger of Hong Kong people in order to cancel or even to postpone the upcoming district council election," Tanya Chan, a pro-democracy MP, told reporters yesterday.

Protesters have also called for a general strike tomorrow and for people to block public transport, although such calls in the past have often come to nothing.

Protesters have thrown petrol bombs and rocks at police who have responded with tear gas, pepper spray, water cannon, rubber bullets and several rounds of live ammunition.

They deny using excessive force.