Daithi McKay, Martina Anderson and Alex Maskey of Sinn Fein

Alex Maskey, Martina Anderson and Daithi McKay represent the party, which voted in January to back police in Northern Ireland for the first time.

Mr Maskey described Sinn Fein's participation as a significant step forward to ensure accountable policing.

Sir Desmond Rea and Barry Gilligan were re-elected as chairman and vice chairman. Sir Desmond said NI was "entering a new era in policing".

"This new board will continue to ensure for all the people of Northern Ireland an accountable, effective, efficient and impartial police service," he added.

BOARD MEMBERS IN FULL DUP Tom Buchanan Jeffrey Donaldson David Simpson Peter Weir Sinn Fein Martina Anderson Alex Maskey Daithi McKay UUP Leslie Cree Basil McCrea SDLP Dolores Kelly Independent Barry Gilligan Rosaleen Moore Mary McKee Gearoid O'hEara Brian Rea Prof Sir Desmond Rea Trevor Ringland David Rose Suniel Sharma

Mr Gilligan said the new board's priority was "engaging communities and building public confidence in policing".

Irish Republic Foreign Minister Dermot Ahern said Sinn Fein coming on board marked another new and positive phase for policing in Northern Ireland.

"The Policing Board has played a pivotal role in building confidence across both communities in the new policing arrangements and in paving the way for recent breakthroughs at the political level," he said.

The DUP is the largest political party on the board, with four members. Sinn Fein has three seats, the Ulster Unionists have two, and the SDLP has one.