Plaid Cymru has beaten Reform UK in the Caerphilly by-election, winning with a majority of 3,848 votes.
Reform UK had been the favourite to win, leading the polls with 42% to Plaid Cymru's 38%. However, Plaid Cymru's Lindsay Whittle won with 15,961 votes, while Reform UK came second with 12,113 votes.
Labour, who had held the seat since 1999, lost with just 3,713 votes. This is the first time in over a century that Labour has lost a Senedd or Westminster election in Caerphilly.
Reform "threw everything" at the Caerphilly by-election and lost
The by-election was triggered by the death of Labour Senedd member Hefin David.
Author's summary: Plaid Cymru wins Caerphilly by-election in major upset.