The Information Commissioner's Office (ICO) has confirmed it will investigate reports that a glitch on the Virgin London Marathon website caused the names and address of all 38,000 runners in the event to be published online.
The issue was first raised when a member of the public discovered entrants' personal details, including celebrities and politicians that had entered, were available on the site and contacted the BBC with the revelation.
As such, the ICO has confirmed it will talk with the organisers of the event to assess the incident and consider any possible action.
"We're aware of a possible data breach involving the website of the organisers of the London Marathon," they said.
"We will be investigating this, before deciding what action, if any, needs to be taken."
The Virgin London Marathon said it would not be commenting on the incident when contacted by V3.
The case echoes that of a recent undertaking handed down by the ICO to Toshiba for a glitch on a competition website it had designed by a third-party that left the names, address and dates of birth available online.
The incident comes at the same time as a Freedom of Information request from network firm Axway revealed 35 per cent of all complaints filed with the ICO relate to incidents involving the disclosure of personal data.
This suggests organisation are still failing to take adequate measures to protect their data despite the risk of fines of up to £500,000 from the data protection watchdog.
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