A man has been arrested after police seized illegal animal specimens including rhino horns and elephant tusks from two addresses in Lancashire.
Officers made the discovery after searching the properties in Burnley.
Several sperm whale teeth and narwhal tusks were also recovered by police.
A 27-year-old man was held on suspicion of offering prohibited species for sale. He has been released under investigation.
The Control of Trade in Endangered Species (Enforcement) Regulations 1997 makes it illegal to sell endangered species and their remains in the UK, including ivory and rhino horns.
Such animal specimens can be extremely valuable on the black market.
Andy McWilliam, from the UK National Wildlife Crime Unit which is working in partnership with Lancashire Police, described the investigation as “complex”.
He added: “We will methodically work through evidence and ascertain what and if any offences have been committed.”
In November last year, a man who tried to sell rhino horns, elephant tusks and hippopotamus teeth worth up to £2m on Instagram was jailed for 14 months.