The incident apparently started when a bar patron made a crude comment about the movie for which Castle-Hughes was nominated for an Oscar, the New Zealand Herald reported today.
Both the actress, 20, and her boyfriend Michael Graves were released by police without charge.
Castle-Hughes said the fight began when someone recognised her at the Pony Club in Customs St and made a derogatory remark about Whale Rider.
She said Graves defended her "in regards to comments made to me that were quite rude about my job, and so from there it became a physical fight".
She said as Graves defended her it got out of hand and there was a lot of people involved.
She said it was "very messy."
She said police took her away because she was in the way as police arrested several people.
"I was given a ride to the station and then allowed to leave, so there were no charges laid and I wasn't given a formal warning or anything."
She would not reveal what the comments were but said they were "quite crude in regards to Whale Rider and they were definitely sexually slanted."
Her boyfriend was slightly hurt but there were no serious injuries on either side, just cuts and bruises, she said.
Castle-Hughes, who has attended Alcoholics Anonymous, said she was not drinking on Saturday night.
She had just finished filming the new television show The Almighty Johnsons.
