NSW detectives believe all the incidents of fruit contamination in the state have been the work of copycats and pranksters and have vowed offenders will feel the full weight of the law.
Needles have been found in more than 20 punnets of strawberries across NSW in the past week after the fruit was first sabotaged in Queensland.
Needles have also been discovered in an apple and a banana, NSW Police confirmed on Tuesday.
Acting Assistant Commissioner Stuart Smith on Wednesday announced a $100,000 reward for information leading to the conviction of anyone who's contaminated fruit in NSW.
He also revealed that investigators believe the original sabotage was confined to three strawberry brands sold in Queensland.
"What we've seen in the state (of NSW) we believe is the work of copycats and pranksters, we've got to deal with it though, the way we deal with any crime," Mr Smith told reporters in Sydney.
The acting assistant commissioner said detectives had already arrested one young boy over behaviour that "could be called a prank".
"Obviously in the last few days we found a young person has admitted to a prank, including putting needles in strawberries, and he'll be dealt with under the youth cautioning system," he said.
In NSW the maximum penalty for deliberately contaminating a food source is 10 years in jail.
Prime Minister Scott Morrison on Wednesday announced urgent and harsh new commonwealth criminal penalties for contaminating food as the ongoing needle crisis brings many Australian farmers to their knees.
NSW Premier Gladys Berejiklian has promised to stand shoulder to shoulder with farmers.
"It is beyond belief that anybody would deliberately sabotage fruit to try and harm people in the process, harm our hardworking fruit farmers and the industry," she told parliament.
"This is a disgusting act designed to instil fear in consumers and to undermine our agricultural industry."
NSW produces around one per cent of Australia's strawberries. The state's strawberry picking season is expected to begin in the next six weeks, according to the premier.