THE seizure of more than 600 credit card knives has police worried that some people might not know the concealable weapons are illegal.
Caboolture Child Protection Investigation Unit officer Ben Hiller said cards seized at Beachmere at the weekend could quite quickly be turned into weapons.
Police allege 629 credit card knives were found after officers searched a Weeroona Ave home on Saturday night.
Officers had earlier in the day located a 15-year-old girl allegedly in possession of 18 credit card knives.
A 48-year-old woman was charged with one count of possession and supply of category M weapons and two counts of unlawfully supplying weapons.
The teenager will be dealt with under the provisions of the Youth Justice Act.
Plain-Clothes Constable Hiller said the location of the teenager led police to the larger find.
Const Hiller said the plastic cards could be folded out to reveal a sharp metal blade, complete with handle.
"Obviously people have mobile phone cases with spots for their cards," Const Hiller said.
"You wouldn't know it was there.
"It is designed to be concealed but it is capable of being a pretty serious weapon."
He was concerned that some people might not know they were illegal.
A quick Google search revealed websites offering the items for sale.
"Just because it is available online doesn't always mean it is legal."
He said those supplying knives could also be charged.
"The important thing is people be aware they are illegal and not purchase them."
He said the investigation into Saturday's seizure was ongoing and the Australian Federal Police or Customs would be informed if the knives were found to have been imported.
"We will track the origins of the ones we located."
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