Hong Kong's best-known young activists were heckled by Chinese nationalists in tense scenes on Sunday as the city's pro-democracy camp tries to claw back lost seats in controversial by-elections.
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.
Wong told reporters that threats to freedoms in the city "prove that it's more necessary for us to vote".
Beijing has become incensed at the emergence of activists advocating independence and views calls for self-determination as part of a dangerous splittist push.
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 on Sunday.
"The election is not just about selecting me as a candidate, it is also about voting for justice," said Au, who stepped in to contest the Hong Kong Island seat after Agnes Chow was disallowed.
Democracy campaigners were deeply angered by the ban on Chow which they said was political screening.
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, cast the opposition as provoking "violence and resistance".
"The by-election is a chance for the silent majority, who are tired of a politicised Hong Kong, who detest those who humiliate the country, to come out and tell those politicians that Hong Kong has no room for them," Chan told AFP.
Democracy camp struggling
Many of the first people to cast ballots at a polling station AFP visited early Sunday were elderly and supportive of the city's pro-Beijing establishment.
"I'm not resistant to democracy and freedom, but I can't accept the independence of Hong Kong," voter Chan Chik-sing, 60, told AFP.
But others said people were angry about inequality.
"If the government's policies were really that good and supported by citizens, the public's satisfaction level for the government wouldn't keep deteriorating," said voter Lilian Leung, who was in her late 30s.
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.
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.
Only half the legislature is 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.