"Through scientific advancement [it] has meant this case has been reopened and led to an arrest," Mr Crawford said.
"In cases like this we are not going to give up or stop trying. We will go to great lengths to apprehend those who commit these terrible crimes."
He hoped the arrest brought reassurance to the victims and the Whangarei community.
In a report printed in the Northern Advocate on January 4, 1991, police appealed for information after a man and a woman had walked down Vine St from outside Pips nightclub to Cafler Park, Water St.
At the time Detective Sergeant John Payne said the woman's attacker allegedly threatened her but had his arm around her shoulder, giving the impression they were on friendly terms.
They had then gone down Water St, through Forum North and to Cafler Park rose gardens and possibly into Second Ave before doubling back to the park.
Police alleged the woman was attacked at the back of the rose gardens near a bridge connecting the park and Second Ave.
On the way to the park the driver of a vehicle stopped in Water St and the driver had spoken to the pair.