Updated

Final results show Hong Kong pro-democracy candidates have won back two of four seats in a crucial by-election in the semiautonomous Chinese region.

According to Monday's tally, the opposition was not able to recapture all its territory, losing some to formidably resourced pro-Beijing rivals in the city's semi-democratic legislature.

The four seats were left empty when a group of lawmakers were expelled following a 2016 controversy over their oaths, which they used to defy China.

Little-known activist Au Nok-hin won a key battleground. He was enlisted at the last minute after officials rejected the pro-democracy camp's marquee candidate for her party's political platform.

The disqualifications of lawmakers and candidates have raised fears among activists and international groups that Hong Kong's Beijing-backed government is taking an increasingly hard line on dissent.