HONG KONG (AFP) - Pro-democracy activists on Sunday accused police of using excessive force against protesters after violent clashes in Hong Kong, as a senior politician said weeks of rallies have reached a "critical moment".
Dozens of police with shields and helmets pushed into a crowd of demonstrators gathered at barricades in the Mongkok district early Sunday, striking at them repeatedly with batons.
Twenty people were injured in a fourth night of violence after three weeks of largely peaceful pro-democracy rallies and road blockades in three busy districts.
Some demonstrators were carried away on stretchers and others treated for head wounds, fractures and bruising.
Police are trying to clear a main thoroughfare, Nathan Road, occupied by demonstrators. They said in a statement on Sunday they had used "minimum force" as protesters "suddenly attempted to charge" their cordon lines.
However protesters said they had done nothing to provoke officers.
"We believe police have violated the principle of using minimum force to deal with peaceful demonstration," said James Hon, of protest group the League in Defence of Hong Kong's Freedom.
He said batons used in this way could cause serious injuries or even deaths.
Finance secretary John Tsang said on Sunday the protests had reached a "critical moment" and urged the demonstrators to retreat.
"I was young before and I have taken part in various student movements," he wrote on his blog. "Retreating is not an easy decision. It takes a lot of bravery. I still believe that you can take the courage to make right decisions at this critical moment."
Hong Kong's government had confirmed earlier Saturday that it would open talks with student leaders on Tuesday.
The moderator of the talks next week between the government and protesters said he would host the meeting in an impartial manner.
Professor Leonard Cheng, president of Lingnan University, said his views on the issue would not affect the talks on Tuesday, RTHK reported on Sunday.
Prof Cheng was an advisor to Chief Executive Leung Chun Ying's election campaign.
Chief Secretary Carrie Lam said both the government and the Hong Kong Federation of Students will each dispatch five people. The dialogue, to be broadcast live, will last for about two hours.
But it is doubtful as to what extent the talks can help resolve the stand-off.
"The government's work on political reform has to be based on the Basic Law and the national legislature's decision. I'm happy to listen to other opinions based on this foundation," Lam said, referring to Hong Kong's mini-Constitution.
The chief executive had also said that the talks must take place within the constitutional framework announced on Aug 31 by China's legislature, the National People's Congress Standing Committee.
This stipulates that there be a nominating committee of 1,200 people, from four pre-determined sectors, to vet candidates for the chief executive election, slated for 2017. Successful candidates must get at least half the votes.
Given that pro-democracy candidates in the past could muster only about 15 per cent of the votes in similarly formed committees, this means only Beijing-approved ones are likely to get through.
The Occupy Central movement is now into its fourth week in Hong Kong. Violent clashes erupted in Mong Kok early on Sunday for a second night, deepening a sense of impasse between a government with limited options and a pro-democracy movement increasingly willing to confront police.