The police arrested a number of people after BirdLife released a film which, it said, showed wild birds being sold at the Valletta open-air market.

The conservation group said the film proved that the illegal trade in wild birds is rampant in Malta's capital city.

The filming took place undercover, BirdLife said.

The birds, which included linnets, greenfinches, serin and chaffinches, were being sold openly by different traders. They could have originated from local trappers or traders illegally importing them from neighbouring countries, BirdLife said.

The footage, taken over the last couple of weeks on different occasions, was passed on to the police and to the planning authority, which carried out a joint operation at the flea market last Sunday.

BirdLife said the police informed it that several dealers illegally selling wild birds were apprehended. They will be charged soon.

The sale of any wild bird is illegal under national legislation. Birds can only be sold if they are shown to be captive bred.

According to law, all birds bred in captivity need to be fitted with rings when they are chicks as a means of verifying that they are not wild. Rings need to be approved by the Environment Protection Directorate within the Malta Environment and Planning Authority.