HANOI: Vietnamese authorities destroyed more than 2,200 kilograms (nearly 5,000 pounds) of seized elephant ivory and rhino horns on Saturday, sending a message ahead of a key international conference the country is hosting next week that they want illegal wildlife trafficking stopped.

The seized horns — estimated to be worth more than $7 million on the black market — came from some 330 African elephants and 23 rhinos that were slaughtered by poachers to meet the demand for ivory, used to make jewelry and home decorations, and rhino horns, in the misguided belief they can cure cancer.

The horns were crushed and then burned on the outskirts of Hanoi, with Vietnam joining 20 other nations in the destroying seized wildlife products.

An international conference on the illegal wildlife trade will be held next week in Hanoi, Vietnam's capital. It will be attended by officials and experts including Britain's Prince William, a vocal critic of the illegal wildlife trade.

Vietnam is one of the world's major transit points and consumers of trafficked ivory and rhino horns.

According to the head of the Convention on International Trade in Endangered Species in Wild Fauna and Flora, or CITES, the destruction of ivory and horns ensures that no one can profit from the contraband and sends a message that "Vietnam is not prepared to tolerate this illegal trade, and that illegal traders now face significant risks along the entire supply chain — in source, transit and destination states."

CITES Secretary-General John Scanlon said in a statement that the age and origin of the contraband can now be identified through forensics, making prosecution and conviction more likely.

"As a result of global collective efforts ... trading in illegal ivory and rhino horn is shifting from low risk, high profit to high risk," he said.

Ha Cong Tuan, Vietnam's vice minister of agriculture and rural development, said at the event: "By organising today's destruction, Vietnam would like to affirm once again that the Vietnamese government is highly determined in implementing laws, international conventions and fighting law violations. It is also a message to those who are thinking of using or trading wildlife products for profit that they must stop; otherwise, they will be severely punished."

The African elephant is facing an unprecedented poaching and trafficking threat. From 2010 to 2012, an estimated 100,000 elephants were killed illegally to meet the global demand for ivory, according to Humane Society International, an international animal protection group.

Over the past decade, poachers killed more than 6,000 rhinos across Africa. In South Africa, 13 rhinos were poached in 2007, but there has been a dramatic increase in poaching since then, and more than 1,300 were poached in 2015 alone, the group said.

"This is just one of many steps that Vietnam has taken over the last three years to combat wildlife poaching," Teresa Telecky, Humane Society International's director, told reporters Saturday. "We are very hopeful that this event will drive the message home to the public that they should not consume rhino horns, they should not consume ivory and get behind the Vietnamese government in trying to stop to this."

In the past two months, authorities in Vietnam have seized 4 tons of ivory smuggled in five shipments from Africa. The destruction Saturday included 2,183 kilograms (4,800 pounds) of ivory and 70 kilograms (154 pounds) of rhino horns.

Vietnam has banned poaching of its own dwindling elephant population, while the Javan rhino was declared extinct in Vietnam in 2011.