A High Court jury has found Colin Jack Mitchell guilty of kidnapping a 23-year-old woman and assaulting her at a West Auckland quarry.

Mitchell, who turns 60 today, of Onehunga, was charged with abduction, wounding with intent to cause grievous bodily harm, and assault with intent to commit sexual violation after the alleged incident in the early hours of Sunday February 26 last year.

After a 12-day trial the jury of four men and eight women deliberated for about six hours before returning to court with a verdict.

They were sent out at 1.09pm yesterday and returned just before midday today.

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They found him guilty on three charges relating to the attack:
• kidnapping with intent to have sexual connection
• wounding with intent to cause grievous bodily harm
• assault with intent to commit sexual violation

As the verdicts were read out Mitchell stood in the dock with his hands clasped in front of him, looking at the ground.

Supporters of the victim gasped in the back of the court as the verdicts were revealed.

The Crown has indicated they will seek preventive detention for Mitchell - an indefinite jail sentence.

His victim was in court to hear the verdict. After the hearing ended she and her supporters hugged police and the Crown prosecutors.

The jury found that Mitchell "took" the 23-year-old "without her consent" as she walked through Grey Lynn following a night out with friends at the annual Pride Parade.

She was driven to the quarry at Riverhead and woke to find a man standing over her with a bat-like weapon.

She was partially clothed and bleeding from a serious head injury.

The woman managed to get away and call police.

After a high profile investigation and appeals for information, Mitchell was identified as the alleged attacker and charged.

Mitchell denied all of the charges.

He said police had the wrong man and he was not the person responsible for the attack.

Mitchell will be sentenced on May 18.