Stephen Flynn is projected to lose his seat in the General Election in what would go down as another devastating blow for the SNP.
The exit poll suggests the party could drop to as few as 10 seats following a near-decade of electoral dominance in Scotland at Westminster.
Casualties could include Flynn, who has been tipped as a future leader by some.
His constituency, Aberdeen South, is due to declare at 3am.
Speaking on ITV, Nicola Sturgeon said: “This is not a good night for the SNP on these numbers.
“I think there will be a question about whether there was enough in the campaign to give out, effectively, a USP to the SNP in an election that was about getting the Tories out and replacing them with Labour.”
She added: “This is at the grimmer end of the expectations for the SNP if the exit poll is right and, from what I’ve said earlier on, I expect it will be.
“This is seismic for Labour. There’s no getting away from that, it’s a massive achievement for Keir Starmer.”
The first result in Scotland is expected to be Rutherglen, which could declare at 1am.
The SNP’s campaign centred around calls for talks on another independence referendum if the party won a majority of seats at the election.
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