"We are appealing to anyone who left the area in a taxi about 2am that night, or has any information, to make contact with us," he said.
The victim was treated for injuries by a doctor. She is been supported by family and support agencies.
The second incident took place around 1am yesterday.
The victim in her 20s has told police she was approached by a man while walking along The Strand in the vicinity of the old Commercial Hotel.
The man took the woman to an isolated area near the Environment Bay of Plenty building on Quay St where she was sexually assaulted.
The victim described the man as Maori of solid build, wearing a caramel coloured hoodie and black pants. She described him as having distinctive eyes with the appearance of being cross-eyed.
The victim was not injured as a result of the incident, although was checked over by medical professionals.
Support services have been enlisted to help her.
Mr Hay said there was nothing to suggest the two incidents were linked.
"Regardless it is concerning to have two incidents within 24 hours and with a short distance of each other," Mr Hay said.
"We would ask people in and around the CBD to be vigilant for any suspicious behaviour and report it to police immediately, no matter how small or insignificant it may seem. Such a call may very well stop someone from being hurt."
Mr Hay also encourages everyone, male and female, to be aware of their personal safety, particularly in the early hours of the morning. Arranging safe transport and making sure someone knows where you are headed and when to expect you back is advised. Friends are also encouraged to stick together and look out for one another.
Contact can be made via the Whakatane Police Station on (07) 308 5255 or passed on confidentially by calling Crimestoppers on 0800 555111.