Hundreds of police forcibly removed kicking and screaming protesters from the Central business district on Wednesday, holdouts of an all-night sit-in on the heels of a mass rally demanding greater democracy from Communist Party rulers in Beijing.
The pro-democracy march on Tuesday, which organizers said attracted more than 510,000 people, and the subsequent sit-in by mainly student groups could be the biggest challenge yet to China which resumed control over the former British colony in 1997.
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Many of the more than 1,000 protesters linked arms in a bid to resist efforts to remove them but they were taken away one at a time, in some cases by three or four police, as activists kicked, screamed and punched before being bundled on to buses.
"I have the right to protest. We don't need police permission," the crowd chanted as they sat sweltering in Hong Kong's summer heat and humidity.
The activists were taken in buses to the police training school in Hong Kong, although it was unclear how many arrests had been made or how long they would be detained.
"Our purpose is first universal suffrage and second to let the government respond to Hong Kong citizens' voice for democracy," said Frank Chio, a representative of the Hong Kong Federation of Students.
"This is only step one, there will be other steps."
In one of the first moves of what is expected to be a hot political summer in Hong Kong, the demonstrators were demanding greater democracy in elections for the city's leader, or chief executive, in 2017.
They want nominations to be open to everyone. China's leaders want to ensure only pro-Beijing candidates are on the ballot.