Police in the north-central Vietnamese province of Thanh Hoa seized 77 pangolins from a car on a highway early Thursday morning.
Officers stopped the vehicle on National Highway 1A at around 2 a.m and found inside the pangolins, which weighed a combined 439 kilograms, including four that had died.
They also found four fake license plates in the car.
Tran Dinh Hung, the driver, failed to produce documents to prove the origin of the animals or the car papers.
He said both the pangolins and the car belonged to a Lao man.
He has been held for further investigation.
The pangolins were handed over to the provincial forest management authorities.