Organisers of the pro-democracy camp's primary elections said that by 6.30pm on Sunday, more than half a million people had cast a ballot to choose who should represent the camp in September's Legco polls.
Au Nok-hin, who helped organise the primaries, said the unexpectedly high turnout had ensured the legitimacy of the exercise.
The former lawmaker said the final turnout could exceed 600,000, far above the set target of 170,000.
Au said voting would end at 9pm sharp, because this time had been programmed into the digital voting system in use. He said even if people were still queuing up outside the many polling stations set up across the city, they would not be able to vote after this time.
"If people intend to vote, please go and do so now rather than be a 'deadline fighter'," Au told reporters.
He said the polls had mostly gone smoothly, with minor interference at a station in Wong Tai Sin after government supporters turned up and "created a nuisance".
Au said the police had "sporadically interfered" in the proceedings, checking the Amoy Gardens polling station in Kowloon Bay to check whether people were following social distancing rules.
He said the results of the primaries would be announced on Monday night at the earliest, and it could be Tuesday if the counting of paper ballots takes longer than anticipated.
Last week, constitutional affairs minister Erick Tsang warned that anyone involved in the primaries, from the organisers to the voters, could breach the national security law.
The police raided the office of a pollster involved in the exercise on Friday night, citing a suspected data leak.
Last updated: 2020-07-12 HKT 18:45
'Over half a million vote in opposition primaries'
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