A report by MPs into the EU Referendum in June has said a voter registration site could have been targeted by a foreign cyber attack. The site crashed before the vote, meaning some people were unable to register.

MPs on the parliamentary public administration and constitutional affairs committee said they could not rule out foreign hackers caused the site to crash on June 7, contrary to a previous government statement that blamed an exceptional surge in demand after a TV debate for the incident.

The “register to vote” site crashed on 7 June last year just before the deadline for people to sign up to vote.

But MPs on the parliamentary Public Administration Committee say a foreign cyber attack could not be ruled out.

The report didn’t name the countries that may have been responsible for the crash and noted there was no direct evidence of foreign interference in British votes, but added the crash “had indications of being a [distributed denial-of-service] DDoS attack.”

David Cameron, the prime minister at the time of the EU referendum, extended the deadline for registering to vote by a few days after the website crashed.

The committee called on the British government to set up a new cybersecurity center to permanently monitor potential attacks targeting elections and referendums, to promote cybersecurity and build resistance to potential attacks.

The website crashed at about 10.15pm on 7 June, 2016,, shortly after a televised debate and amid social media campaigns to get people to register to vote ahead of the midnight deadline. Official figures suggest 525.000 people applied to register to vote that day.