The Scottish Conservatives have been mocked for spending thousands on a Facebook advert that was mostly viewed by voters in England.
The Tories spent £3,000 on a digital ad that claimed Douglas Ross's party was the "best way to beat the SNP".
Facebook advertising records show it reached one million registered users - but 80 per cent of them were in England, and just nine per in cent in Scotland.
The SNP claimed it was "the digital equivalent to the Scottish Tories paying for ads in English newspapers".
It comes as the Conservatives are braced for losses across the country as council election results are declared later today.
Facebook advertising allows customers to target their adverts to individual countries, cities or even towns.
SNP MP Deidre Brock said the gaffe smacked of "incompetence".
A Tory source blamed a "cockup" at party headquarters in London.
Brock said: "Douglas Ross has had an awful campaign - but this level of incompetence demonstrates just how badly his campaign has come off the rails.
"The Scottish Tories have splurged thousands of pounds on digital election ads and less than one in 10 of the people that have seen them are voters in Scotland.
"This is the digital equivalent to the Scottish Tories paying for ads in English newspapers.
"This massive waste of cash just about sums them up - and they are totally out of touch with the realities of the cost-of-living crisis.
"I’m confident that the vast majority of voters across Scotland will have sent Boris Johnson a message and rejected them at the ballot box."
A Tory source told the Record: "This was a cockup by the party south of the border who somehow managed to target one advert across the UK despite clear instructions to target it only to people in Scotland.
"Clearly, we are not happy at their incompetence."
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