Nearly 80,000 names have been struck off a petition urging a second EU referendum after they were found to be fraudulent.
The online petition has been signed more than three million times, even though an expert suggests it will have no effect.
The House of Commons Petition Committee said it removed about 77,000 signatures which were added "fraudulently" and it would check for suspicious activity.
Committee chairwoman Helen Jones MP said: "People adding fraudulent signatures to this petition should know they undermine the cause they pretend to support."
She added the committee would meet next week to discuss whether MPs will debate a possible second public ballot. The online petition has called for the Government to implement a rule that "if the Remain or Leave vote is less than 60% based on a turnout less than 75%, there should be another referendum".
Britain's leading elections expert, Professor John Curtice, said the petition was likely to come to nothing. "It has passed the 100,000 mark for it to be debated in Parliament. All that means is that some MPs will say, 'It's a terrible shame', others will say, 'Hallelujah'. Then that's the end of it," he said.