HONG KONG: More than half a million Hong Kong people voted in primaries held by pro-democracy parties to choose candidates for upcoming legislative elections, organisers said on Sunday.

The high turnout for the unofficial poll came despite a government warning that it could be in breach of a tough new security law imposed on the city by Beijing.

People queued in the intense summer heat at more than 250 polling stations across the city for the two-day vote which opened hours after police raided an opinion pollster helping to conduct the primaries.

After polls closed at 9:00 pm on Sunday, organisers said more than 610,000 people had cast their ballots, including 590,000 digital votes and 21,000 on paper.

"Under the vicious national security law, many people worried if such participation would risk violating the law but many people still came out," said organiser and legal scholar Benny Tai.

"I would like to send my respects to everyone," the democracy campaigner said.

The winning candidates are expected to be announced on Monday evening and be endorsed to run for seats in the city's 70-member legislature in September.

"Under the cloud of the national security law, nearly 600,000 people came out and voted - this is where we can see the courage of Hong Kong people," former legislator and primary organiser Au Nok-hin said earlier before all the votes were tallied.