About 100 protesters surrounded a Hong Kong police station on Thursday night demanding the release of the founder of a banned pro-independence party, local media reported.

Andy Chan, the head of the Hong Kong National Party, was arrested hours earlier along with seven others at an industrial building in the semi-autonomous Chinese territory, police said.

Police claimed they also seized weapons and suspected petrol bombs during the raid in the New Territories district of Sha Tin. Making or possessing explosives illegally can carry a sentence of up to 14 years in jail.

Read more: Hong Kong pro-democracy movement — going from strength to strength

National security threat

In the first ban since the former British colony returned to Chinese rule in 1997, Chan's party was outlawed last September on the grounds it posed a national security threat.

Despite having just a few dozen members, the party's existence has infuriated Beijing, which has refused demands for independence or greater autonomy in Hong Kong.

Read more: China backs police in Hong Kong unrest

Hong Kong and Beijing authorities have signalled a hardening stance towards the sometimes violent protests

The arrests came on the eve of fresh anti-government demonstrations, this time by Hong Kong civil servants and medical workers.

Thousands of people are due to rally on Friday night in support of the massive protest movement that erupted two months ago and that has seen millions take to the streets.

Initially demanding the withdrawal of a proposed bill that would have allowed the extradition of suspects to mainland China, the protests have since morphed into a wider call for more democratic reforms.

Protests more vexed

The protests have turned increasingly violent, and the territory's government has struggled to maintain law and order. Beijing, meanwhile, has looked on anxiously at the worst political crisis since the handover.

Hong Kong enjoys a high degree of autonomy from China under the "One Country, Two Systems" mechanism, which is currently due to last until 2047, but many fear this autonomy is being eroded.

Read more: Hong Kong protests: Is the government losing control of law and order?

China's top diplomat Yang Jiechi on Friday once again accused the United States of "fanning the flames" of the protests.

The state councilor was cited by the official Xinhua News Agency as saying several Western governments were arranging meetings with protest leaders and encouraging them to undermine "prosperity, stability and security" in the Chinese territory.

Trump calls protests 'riots'

US President Donald Trump, meanwhile, has said it is up to Beijing to respond to the "riots" gripping the territory.

"Hong Kong is a part of China, they'll have to deal with that themselves," he told reporters in Washington.

On Wednesday, 44 people were charged in a Hong Kong court with rioting over their role during recent violent protests that saw activists clash with police near Beijing's main representative office in the heart of the city.

mm/aw (AFP, Reuters)

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