Queensland police are yet to determine who is spiking store-sold strawberries with needles.
But they're hopeful a $A100,000 reward for information will lead to the capture of the culprit or culprits.
Consumers have been told to cut their strawberries up amid fears six brands across four states have been targeted with needle insertion.
"Our investigation is ongoing. It's fairly complex and fairly large because of the itinerant nature of employees in the industry," Detective Superintendent Terry Lawrence said.
"I won't go as far as saying we have specific leads.
"If we can narrow it down to a smaller geographical location and particular farms, that would be great for us."
Fruit sold under Berry Obsession, Berry Licious and Donnybrook brands originating from Queensland have been withdrawn from retailers.
NSW police have warned that fruit sold under the Love Berry, Delightful Strawberries and Oasis brands had needles inserted by a possible copycat.
A fresh report of a contamination in Townsville is being investigated, Queensland police said, following instances elsewhere in the state, as well as Victoria and NSW.
But authorities have stopped short of discouraging consumers from buying strawberries.