Border officers in Vietnam have seized 9.4 kilograms of rhino horn from a man in Tay Ninh province, who claims he transported the contraband, valued at $500,000, unwittingly from Cambodia, according to Vietnamese media.

Suspect Do Khac Duy, was arrested on May 27 at the Ta Han border post and said he was unaware of what was inside a package given to him in Cambodia by a man named Ha, who he said hired him to transport clothes, according to news site ThienNhien.net.

In the context of recent ivory seizures in Cambodia, the case offers further evidence the Kingdom is being used as an overland trafficking route, said Thomas Gray, Manager of Species and Landscapes Programs for WWF Greater Mekong.

“The smuggling networks have clearly identified that Cambodia is maybe a relatively easy place to bring products in from Africa and then send them to the markets in Vietnam and China,” Gray said.

Giovanni Broussard, of the UN Office on Drugs and Crime’s Southeast Asia office, said the haul could fetch more than $500,000 in China or Vietnam, where rhino horn is used in traditional medicine, as an aphrodisiac and, increasingly, as a status symbol. The demand was decimating rhino populations, he said. “The number of rhinos that have been poached in South Africa went from a little bit more than 10 in 2007 to 1,215 in 2014, so the number is growing exponentially.”

Broussard said UNODC was just last week training border officers in Tay Ninh, which borders Mondulkiri, about detecting illegal wildlife and would monitor the most recent case.