The online petition has more signatures than any other on the House of Commons website. Since it passed 100,000 names, Parliament will consider it for debate, the BBC reports.
However, some media outlets were reporting Sunday that many names were fake. The House of Commons petitions committee tweeted that it had "removed about 77,000 signatures which were added fraudulently" and said "We will continue to monitor for suspicious activity."
The Telegraph reported that while hackers in online chatroom 4 Chan were claiming responsibility for the fake names, the petitions committee had denied evidence of hacking.
The online petition site, hosted by the House of Commons website, crashed Friday because so many people tried to access it, the Associated Press reported. The petition also called on the government to implement a rule saying that if either side won less than 60% of the vote based on a voter turnout of less than 75%, there should be another referendum.
The voter turnout on Thursday was 72%, and "leave" won with 52% to 48% for "remain."
Officials said Friday that they saw unprecedented interest in the measure. Prime Minister David Cameron said there would be no second referendum. However, Parliament member David Lammy has tweeted "We can stop this madness through a vote in Parliament" and that there should be a vote in Parliament next week on whether to move forward with Brexit.