The SNP has ousted Scottish Labour leader Jim Murphy as it stands on the verge of a historic landslide general election victory in Scotland.
The party is set to almost wipe out Labour in Scotland, with Douglas Alexander and Margaret Curran also losing their seats.
The SNP won by 10,000 votes in Kirkcaldy and Cowdenbeath, which had previously been held by Gordon Brown.
And it won Glasgow North East with a record swing of 39.3%.
By 04:45, the SNP had won 50 of the 52 seats to have declared in Scotland, making it by far the party's most successful general election ever. Its previous best was in October 1974, when it won 11 seats.
The SNP has won all seven seats in Glasgow from Labour, while former party leader Alex Salmond will be returning to the House of Commons after winning the Gordon constituency from the Liberal Democrats.
The only seats which the SNP has not won so far are Orkney and Shetland and Edinburgh South, where Liberal Democrat Alistair Carmichael, the former Secretary of State for Scotland, and Labour's Ian Murray managed to hold on.
Electoral expert John Curtice told the BBC it was possible the SNP would win more than half of the votes in Scotland, a feat not achieved by any party since the Conservatives won 50.1% in 1955.
An exit poll has predicted the SNP would win 58 of Scotland's 59 seats, while the Conservatives will be the largest party across the UK.
In East Renfrewshire, the SNP's Kirsten Oswald defeated Mr Murphy - who had been defending a majority of 10,400 - by 3,718 votes.
The defeat will leave major questions about whether Mr Murphy can continue as Scottish Labour leader, with former Labour MP Ian Davidson - who lost his Glasgow South West seat to the SNP's Christopher Stephens - having already called for him to resign.
Mhairi Black, who becomes the UK's youngest MP, overturned former shadow foreign secretary Mr Alexander's majority of 16,600 in Paisley and Renfrewshire South to win by 5,684 votes - a swing of 27% from Labour to the SNP.
Labour's former Shadow Scottish Secretary Margaret Curran was defeated by more than 10,000 votes by the SNP's Natalie McGarry in Glasgow East.
Alan Brown had earlier been elected as the new SNP MP for Kilmarnock and Loudoun - which was the first seat in Scotland to declare - with 30,000 votes.
His tally was almost double that of Labour's Cathy Jamieson, who won the seat in 2010, but was heavily defeated this time round after returning 16,362 votes.
The SNP has also gained seats including Dunbartonshire West, Falkirk, Ochil and South Perthshire, Dundee West and Edinburgh South West, which had previously been held by former Chancellor Alistair Darling, from Labour.
The SNP's John Nicolson defeated Lib Dem incumbent Jo Swinson in Dunbartonshire East, while Marion Fellows defeated Labour's Frank Roy in Motherwell and Wishaw.
Elsewhere, Senior Liberal Democrat sources have admitted that former Chief Secretary to the Treasury Danny Alexander will lose his seat.
SNP leader Nicola Sturgeon, who is at the Glasgow count at the Emirates Stadium, told the BBC that Labour had been "losing the trust of the people of Scotland over a period years".
She added: "What we're seeing tonight is Scotland voting to put its trust in the SNP to make Scotland's voice heard, a clear voice for an end to austerity, better public services and more progressive politics at Westminster. That's what we now intend to do."
Throughout the election campaign, Ms Sturgeon had been hoping to form a "progressive alliance" with other parties to bring about change at Westminster.
But with the Conservatives on track to be the largest party again, she insisted Labour could not blame her party for its failure to win across the UK.
(BBC)