Adelaide police are investigating whether someone hacked the City To Bay Fun Run website and took personal details.
Part of the website has been taken offline and online entries suspended because of the possible security breach.
The fun run committee said an unauthorised person might have viewed the names, email details and in some cases phone numbers of as many as 12,000 participants.
Read more on ABC (AU). There is no notice or alert posted on the event’s website as of the time of this posting.