Sinn Féin becomes biggest party in local government in Northern Ireland

Nationalist party made sweeping gains including unprecedented breakthroughs in Down and Antrim

• Northern Ireland council elections: all the latest results

Sinn Fein has become the biggest party in Northern Ireland local government after stunning gains in council elections.

It swept past the Democratic Unionist party (DUP) and became the first nationalist party to hold the most council seats, delivering a political and psychological blow to unionism.