The Earthquake Commission's chief executive is blaming human error for a privacy breach in which thousands of people's private information was emailed to someone outside the organisation.
Ian Simpson says the email system, Outlook, automatically completed an address that was not the person within the organisation that the information was intended for.
Details relating to 9700 were sent.
Ian Simpson says he apologises unreservedly for the breach, which he says only affects customers in the EQC Canterbury Home Repair Programme whose repairs are yet to begin.
He told Checkpoint the Outlook system may need to be replaced to avoid such a situation happening again.
Mr Simpson says the email recipient has agreed to destroy all the material, which did not include customers' names.
He says most of the information would require knowledge of EQC's internal workings to interpret it.
The minister responsible for the commission, Gerry Brownlee, says he has been told that a staff member sending an internal email made the mistake and that it was caused by an automatic correction of an address going unnoticed.