Ulster Unionist Party leader David Trimble has lost his Westminster seat in Upper Bann to David Simpson of the Democratic Unionist Party.
The result is a body blow both to Mr Trimble and his party which looks likely to have only one MP in the House of Commons, in the form of Lady Sylvia Hermon of North Down.
Confirming a pattern of huge gains for the DUP at the expense of the UUP, Mr Simpson won comfortably with 16,679 votes, compared to Mr Trimble's 11,381. Mr Trimble, who has held the Upper Bann seat for 15 years, must now consider his position as leader of the UUP.
Meanwhile, the SDLP leader Mark Durkan has seen off the challenge of Sinn Féin's general secretary Mitchel McLaughlin and won the Foyle seat with a majority of more than 6,000 votes.
Mr Durkan retained the seat for the SDLP with a larger majority than many commentators had been predicting.
While the SDLP vote clearly held up it appears Mr Durkan may also have benefited from tactical vote from unionists.
The DUP has recorded substantial gains across the North. Mr Paisley saw a 4.9 per cent increase in his own vote and secured a majority of 17,965 in North Antrim.
Large gains for his party were also seen in East Antrim where UUP Chief Whip Roy Beggs had his seat taken by the DUP's Sammy Wilson. Mr Wilson won the seat with a majority of 7,304.
In North Belfast, Nigel Dodds of the DUP was elected with a majority of 5,188 ahead of Sinn Féin's Gerry Kelly. Peter Robinson, meanwhile, retained his seat in East Belfast with a comfortable win over Reg Empey of the UUP, while his wife Iris was returned in Strangfor. Gregory Campbell retained his seat in East Derry and in South Down Willie McCrea of the DUP regained his seat he lost in 2001.
Jeffrey Donaldson, who defected from the UUP, retained his Lagan Valley seat. Mr Donaldson received 23,289 votes, well ahead of the next closest, Basil McCrea of the UUP who got only 9,172 votes.
In the South Belfast constituency the SDLP's Alasdair McDonnell was the surprise winner ahead of the DUP's James Spratt, taking the seat from the UUP.
The SDLP's Eddie McGrady also held onto his seat in the South Down constituency.
In Fermanagh/South Tyrone Sinn Féin's Michelle Gildernew retained her seat she won in 2001 with 18,638 votes ahead of the DUP's Arlene Foster, who received 14,056 votes.
In Newry and Armagh Conor Murphy of Sinn Féin took Seamus Mallon's old seat by more than 8,000 votes ahead of the SDLP's Dominic Bradley.
Martin McGuinness took the final seat in the Northern election when he won the Mid Ulster constituency with an 11,000 majority over the DUP's Ian McCrea.
Sinn Féin president Gerry Adams, meanwhile, took 70.48 per cent of the vote in West Belfast, some 24,348 of the ballots cast and a 4 per cent increase in his majority. The next nearest candidate was Alex Attwood of the SDLP who took 14.57 per cent, or 5,033 votes. Diane Dodds of the DUP scored 10.57 per cent and Chris McGimpsey of the Ulster Unionist Party received 2.26 per cent of the votes cast.
Mr Adams first won the seat in 1983 and has held it since - with the exception of the 1992 election, when his seat was taken by the SDLP's Joe Hendron. West Belfast was the first of the 18 Northern Ireland seats at Westminster filled as counting commenced this morning.
The UUP's share of the ballot in West Belfast was down by some 3.95 per cent.
