Sex abuse and assault victims who went to ACC (Accident Compensation Corporation) for help were horrified upon learning that ACC Minister Judith Collins has demanded an urgent report into allegations that strictly private details of thousands of ACC claimants somehow wound up in the hands of an unauthorised recipient.

Privacy Commissioner Marie Shroff told the Dominion Post the breach was likely one of New Zealand's most serious.

Fairfax Media reported an estimated 9000 ACC claimants, including sexual abuse and rape victims, had their details emailed to someone who should not have received them.

The details include full names and the nature of individual's claims - including those of 250 people handled by the ACC's sensitive claims unit.

Ms. Collins on Tuesday morning asked ACC chief executive Ralph Stewart for a report into the matter.

APNZ spoke to a woman from Auckland who has a historic sensitive claim with ACC. She said she was horrified by the possible breach of her details when a lot of her family members have no idea of her ordeal and what she has gone through in the past. To make matters worse, her daughter is getting married later this year, and she could barely imagine how this family affair would turn out once her secrets are revealed.

"Things are put aside, and you're working through things and now it's all coming back,'' she told APNZ.

The Auckland woman's claim is related to an incident in 1993 involving her then father-in-law.