The Electoral Commission has instituted an inquiry to establish the circumstances of the unauthorised circulation of party candidate lists and the person or persons responsible.

On Saturday, the Commission reported that it had become aware of lists of candidates that were being circulated on social media platforms.

Briefing the media in Pretoria on Monday afternoon, the Electoral Commission Chief Electoral Officer Sy Mamabolo said following investigations over the weekend and early hours of Monday, the Commission was in a position to give a preliminary report.

The investigation narrowed the source of the disclosure to a workstation that had been used to generate and store reports.

Later, the said reports were deleted from the workstation.

"Earlier today [Monday] the workstation was secured and imaged in the presence of the staff member whose credentials were used to generate the reports. A forensic analysis of the computer is currently under way," said Mamabolo.

Mamabolo said the Commission reiterates its regret for the unauthorised disclosure of the lists and the disclosure of personal information of candidates on those lists.

"The Commission continues to cooperate with the Information Regulator in this regard," he said.