Police say even they were surprised by the size of this potential weapon handed over by a member of the public.
He took it to a Cambridgeshire police – and officers stared at it in amazement.
A police spokesperson said: “Our officers were taken by surprise when a man handed this rather larger than average knife into the police station.
“The weapon falls under new laws which make it illegal to own such items in a private place.”
Police say if you are unsure of the new rules then check them out.
Police say knife and gun crime is relatively rare in Cambridgeshire.
“We offer advice and information to help prevent knife and gun crime and educate members of the public,” said the spokesperson.
"If you need to share information with us or have any concerns about knife and gun crime, please report a concern to us online or call 999 in an emergency."
You can also report anonymously by contacting Crimestoppers.
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