Britain's Euroskeptic UKIP party has made its strongest ever gains in local elections, harnessing discontent with immigration and established politicians to grab support from Prime Minister David Cameron's Conservatives and the opposition Labour party.
The surge by the U.K. Independence Party, which wants Britain to leave the EU, will pile pressure on Cameron to toughen his stance on Europe and alarm some Conservatives who worry UKIP could scupper their hopes of winning the 2015 national election.
If the trend indicated by partial results is mirrored in the elections for the European Parliament, also held Thursday in Britain, the votes will mark the biggest electoral triumph to date for UKIP's leader, Nigel Farage.