Labour's election supremo Douglas Alexander has lost his seat to a 20-year-old university student standing for the SNP.
In the first high-profile Labour casualty of the night in Scotland, the Shadow Foreign Secretary lost to Mhairi Black in Paisley and Renfrewshire.
Ms Black, a third year politics student at Glasgow university, will become the youngest MP since 1667 after the sensational result.
She turned Mr Alexander's majority of more than 16,000 into a 5,684 lead for her party, with almost 51 per cent of the vote.
"Thank you to everyone who turned out and voted for me and helping me win the Paisley and Renfrewshire South," Ms Black tweeted after the announcement.
She added in a victory speech: "The people of Scotland are speaking and it's time for their voice to be heard at Westminster.
"I make this promise...that is exactly what I plan to do."
Mr Alexander, who was Labour's election coordinator, conceded the results were pointing to a "difficult night" for his party.
"Scotland has chosen to oppose this Conservative government but not place that trust in the Labour Party," he said. "It will be our responsibility to re-win that trust in the months and years ahead."
General election 2015 - in pictures
It comes as the SNP are on course for a landslide as Labour face the prospect of near obliteration north of the border.
Former Prime Minister Gordon Brown's Kirkcaldy seat also fell to the SNP.
