HONG KONG (Reuters) - Chinese authorities seized 7.48 tonnes of smuggled ivory tusks last month, the biggest haul in recent years, as Beijing steps up a campaign against illegal wildlife trafficking.

The seizures came during an operation against an international criminal gang “that has long been specializing in smuggling ivory,” the customs administration said on Monday.

China, the world’s largest importer and end user of elephant tusks, banned ivory sales in the country in 2017.

Demand for ivory from Asian countries such as China and Vietnam, where it is turned into jewels and ornaments, has led to a surge in poaching across Africa.

Since January, China has seized 8.48 tonnes of ivory and ivory products and more than 500 tonnes of endangered species, the customs administration said.

The ivory tusks are part of a flurry of seizures - from rhino horns to pangolin scales - in Hong Kong, Singapore and Vietnam in recent months.

Much of the trade supplies the traditional Chinese medicine industry, with demand for treatments using animal products driving a surge in illegal trafficking of wildlife.

Environmental groups have urged authorities to go beyond the seizure of animal products and to prosecute wildlife criminal networks.