Villagers in Hoi Ha Wan alerted police after a group of men began piling boxes on the beach. When one resident asked what the boxes contained, she was told it was a cargo of chicken wings.

Some men fled when police arrived and opened a box to find it full of pangolin carcasses. Three men aged 28 to 36 were arrested on suspicion of possessing a protected wildlife species without a licence and were released on bail.

Pangolins are small, lizard-like mammals covered with scales. They are eaten as a delicacy on the mainland, where their flesh is believed to have medicinal and aphrodisiac qualities and sells for more than $120 a kilogram.

There are some pangolins in Hong Kong but police sources said it was believed the pangolins found at Hoi Ha Wan were imported from Taiwan - where they are not subject to export restrictions - with the intention of smuggling them into the mainland.

'I doubt there are 1,800 pangolins in the whole of Hong Kong,' one source said.

'These must have come in from outside and they would sell for a very handsome price on the mainland.'

Agriculture, Fisheries and Conservation Department officers were investigating the source of the haul. A spokesman said that if convicted, the smugglers faced a maximum $5 million fine or two years in jail.

Groups including WWF Hong Kong and Friends of Hoi Ha called for vigilance against smuggling protected species.