The department’s drug division inspected three suspicious parcels, two from Portugal and one from Germany, on May 8 and discovered 7.4 kilograms (16.3 pounds) of synthetic pills inside.

They identified them MDMA, also known as ecstasy. The drugs had been hidden inside stuffed animals, carton boxes, vinyl players, and bags of clothes.

The packages had been as gifts to fake recipients and addresses. If undiscovered by the police, the people involved in the operation would have found ways to receive the package via some delivery order tricks, customs officials said.

Heroin has long been the common drug in Vietnam, mostly among older men, but the use of synthetic drugs is on the rise, especially among a growing class of hard-partying youth.