HONG KONG (AFP) - Hong Kong police have arrested at least 22 people during a series of protests targeting a senior Chinese official visiting the city, authorities said on Tuesday.

The city has been plunged into political crisis after pro-democracy activists vowed to take over the streets of the city's financial district following Beijing's refusal to grant citizens full universal suffrage.

In the kind of scenes that would be unthinkable on the mainland, Li Fei, a senior member of China's rubber stamp parliament, has been dogged by angry demonstrations throughout his visit to the former British colony - including lawmakers heckling him during a speech on Monday.

Li is in town to explain China's controversial proposal to control who stands for the top post in the city's next leadership election, a decision that has prompted pro-democracy activists to embark on what they describe as a new "era of civil disobedience".

Protesters have kept a vigil outside Li's hotel with renewed scuffles breaking out late Monday evening.

"During the protest, the participants forcibly pushed the mills barriers, charged the police cordon line and dashed onto the carriageway," police said in a statement published on Tuesday.

Officers made 19 arrests outside the luxury Grand Hyatt Hotel in the Wan Chai district of the city late Monday. Eighteen of the protestors were arrested for "unlawful assembly", the statement said. The other activist was arrested for obstructing a police officer.

Earlier on Monday, police used pepper spray on demonstrators at a convention centre on the outskirts of the city where Li gave a speech that was punctuated by regular interruptions by protesters and pro-democracy lawmakers.

Three people were subsequently arrested for disorder in a public place, police said.