Hong Kongers are heading to the polls Sunday in the first major election since 2014 pro-democracy street protests.

A new crop of radical activists are challenging both pro-Beijing rivals and Hong Kong's mainstream pro-democracy parties for seats in the Legislative Council, or Legco.

A series of vandalized posters are a sign that the elections are the most contentious since the 1997 British handover of the city to China.

Many of the candidates in the defaced posters are from the new wave of pro-democracy activists who, unlike their older established mainstream counterparts, reject the idea that Hong Kong is a part of China and support more confrontational tactics and radical action in their fight for full democracy from Beijing.

A key theme of this year's vote is a growing call for independence from China. Such talk was once considered unthinkable but has become commonplace as residents fret over Beijing's tightening. Some of the more radical candidates want Hong Kong-focused localism and others desire full autonomy.

Pro-democracy candidates agree on the need for direct elections for Hong Kong's top leader, currently hand-picked by a committee of mostly pro-Beijing elites. Chinese communist leaders had promised to allow elections but insisted on screening out unfriendly candidates, a stance that sparked the 2014 protests and left Hong Kong's democratic development in limbo.