A high-level Chinese government official has addressed an economic summit in Hong Kong amid calls for greater autonomy for the former British colony or even independence from the mainland.

Thousands of police were deployed across Hong Kong on Wednesday to keep protesters demanding free elections at bay as Zhang Dejiang spoke at a conference on Beijing's One Belt, One Road initiative.

The initiative is a plan for a new Silk Road and economic belt spreading from western China to Central Asia and Europe.

Zhang Dejiang, who is head of China's parliament and the point person on Hong Kong and Macau affairs, arrived on Tuesday for a rare visit.

He has pledged to listen to residents' concerns about the special administrative region's relationship with China.

Hong Kong media reports said up to 6,000 police officers would be deployed for Zhang's three-day visit.

Police on alert

Plainclothes and uniformed police were on alert close to parts of the Asian financial centre that were crippled by pro-democracy protests in late 2014.

Those protests presented China with one of its greatest political challenges in decades.

On Wednesday, protesters chanted for Hong Kong leader Leung Chun-ying to step down, while others held up a black banner calling for an end to dictatorial rule and to "stop interfering with Hong Kong affairs".

One small group of protesters burned a portrait of Zhang and chanted "Zhang Dejiang get the hell out of Hong Kong".

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They also demanded the release of all political prisoners and true universal suffrage for Hong Kong.

Others waved yellow umbrellas, a symbol of the so-called Occupy demonstrations in 2014 when protesters used them during clashes with police who fired tear gas.

Democracy activists and pro-China groups traded insults close to the conference centre where Zhang was speaking, heckling and swearing at each other.

Al Jazeera's Sarah Clarke, reporting from Hong Kong, said: "With just three protest sites set up within a secure zone in the central part of the city, fighting between the pro and anti-China groups wasn't a surprise.

"But with the entire area barricaded and well away from the Chinese state leader, there was little chance these protesters would be heard."

Protesters sceptical

In a move that some see as a way of addressing the city's polarisation, Zhang said he will meet a group of pro-democracy politicians before an official banquet on Wednesday night.

But most protesters do not believe the Chinese leader is willing to listen to them.

"The Chinese party and the Hong Kong government are branding this as extending an olive branch to the opposition," Avery Ng, of the League of Social Democrats, told Al Jazeera.


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"But I have to remind the world that this is a fake olive branch."

The official China Daily said in an editorial that Zhang's visit comes at a "crucial" time to underscore China's support and commitment to maintaining Hong Kong's stability and prosperity.

"With an election for the the next leader of Hong Kong due early next year, the fight by some form of greater democracy is not going away," Al Jazeera's Clarke said.

"It looks like Hong Kong is on a collision course with its motherland."

Concerns have been growing over media freedom in Hong Kong with China's growing control [AFP]

Source: Al Jazeera and agencies