Vietnamese customs officers have seized one ton of contraband elephant tusks stashed in three Cambodia-bound containers in transit at a port in Ho Chi Minh City.

The local customs checked one of the three containers at Cat Lai Port on Monday afternoon and discovered almost 500kg of smuggled ivory inside.

Their inspection on Tuesday morning showed that another 500kg was put in the other two.

The huge volume of ivory was stashed in wooden bars in the three containers, customs officers said.

The bill of lading showed that the consignor was from Africa and the consignee was a firm in Cambodia.

The three containers had been declared to house wood.

Ho Chi Minh City customs officers had confiscated nearly five tons of tusks and pangolin scales smuggled via Cat Lai Port before the latest case.

On November 12, Vietnam destroyed nearly 2.2 tons of seized elephant ivory and 70kg of rhino horns from 23 rhinos and about 330 African elephants, in one of its strongest moves yet to stop illegal wildlife trafficking, according to Reuters.

"Your first ever destruction of illegally traded ivory and rhino horn at the weekend provides a powerful example ahead of this conference, and we look forward to hearing about the further actions you plan to take," Reuters quoted Prince William as telling a conference in Hanoi this month, when he visited Vietnam to raise awareness of wildlife protection.