Sunday’s vote once more exposed the city’s deep political divide and comes as China takes an increasingly tough line against any challenges to its sovereignty.
High-profile candidate Agnes Chow was barred from standing because her party promotes self-determination for the semi-autonomous city.
Soon after polls opened, several men and a woman heckled Chow as well as leading pro-democracy activists Joshua Wong and Nathan Law near a polling station where they were supporting pro-democracy candidate Au Nok-hin, according to an AFP reporter at the scene.
One of the men barged into Wong, who led mass demonstrations in 2014 calling for greater democratic freedoms.
“Traitors and running dogs!” a man repeatedly yelled — insults commonly used by Beijing loyalists against political opponents — while others hurled obscenities.
Wong told reporters that threats to freedoms in the city “prove that it’s more necessary for us to vote”.
Beijing has been incensed at the emergence of activists advocating independence and views calls for self-determination as part of a dangerous splittist push.
The vote comes on the day the Chinese Communist Party decided to give President Xi Jinping a mandate to rule for life, fuelling fears that Hong Kong’s freedoms will come increasingly under threat.
The by-election was triggered after Beijing forced the disqualification of six rebel lawmakers who had swept to victory in citywide elections in 2016.
Some were former protest leaders, others openly advocated independence. All were ousted from their posts for inserting protests into their oaths of office.
Four of the six vacant seats are being contested Sunday.
Au said it was a “vote for justice” after stepping in to contest the Hong Kong Island seat after Agnes Chow was disallowed.
The seat was originally held by Law, also a 2014 protest leader, who was among the six thrown out of office.
But pro-establishment politician Judy Chan, standing against Au, said the vote was a chance for “the silent majority, who are tired of a politicised Hong Kong, who detest those who humiliate the country” to push out destabilising opponents.
– ‘Systemic violence’ –
Democracy activists urged voters to the polls as by 6:30 pm (1030 GMT) only 31 percent of the 2.1 million eligible had turned out, lower than the rate in the landmark elections of 2016.
Some voters Sunday hoped a legislature weighted more towards the pro-Beijing establishment would help on livelihood issues in a city with a huge wealth gap and poverty issues.
Some accepted that Beijing was in charge.
“China is the big brother now,” said a retired policeman who gave his name as Kwan.
But others were worried about rule of law in the city.
“I want my children and grandchildren to live in a place with a fair system,” a banker who gave his name as Hong, 56, told AFP.
One 25-year-old university student named Lui slammed the government for using “systemic violence” to disqualify legislators.
The six lawmakers were retrospectively barred from office by Hong Kong’s high court after Beijing issued a special “interpretation” of the city’s mini-constitution, stipulating legislators had to take their oath “solemnly and sincerely” or face being banned.
Pro-independence lawmakers had inserted expletives and waved “Hong Kong is not China” banners during their swearing in. Others added phrases supporting the democracy movement.
The pro-democracy camp has come under increasing pressure since the failure of the Umbrella Movement to win political reform, with some leading activists jailed on protest-related charges.
Even if it wins back all four seats Sunday, it faces an uphill struggle in a legislature which is only half elected, with the rest selected by traditionally pro-establishment interest groups.
Of 70 seats, the democracy camp currently holds 24, only just clinging on to the one-third needed to veto important bills.