Polling cards have been sent to over 3,000 people who are not eligible to vote in the upcoming EU referendum, the British elections regulator has revealed.
The Electoral Commission, an independent body that regulates elections, put the error that saw 3,462 polling cards incorrectly issued down to a software provider.
It added that any postal votes that were used by any wrongly-enfranchised electors would be voided.
Affected voters would be written to, the Commission added, with a full explanation of the mistake and told they can not vote on June 23.
In a statement, a spokesperson for the body said:
"The Commission can today confirm that according to information it has received so far, 3,462 electors were affected by this issue.
"We are still waiting for confirmation from 6 local authorities about whether they were affected and, if so, the figures will be updated once we receive this information.
"The software provider has resolved the issue which means that, if any postal votes have been issued to these electors, they will be cancelled and none of these electors will be shown as eligible on the electoral registers to be used at polling stations on 23 June.
"All of the affected electors will also be written to by their local Electoral Registration Officer with an explanation of what happened and will be told that they will not be able to vote at the referendum.