Customs officials in Ho Chi Minh City seized an illegal shipment of radar scramblers designed to foil traffic police on Monday.
The personal shipment was registered to an unidentified person from District 3.
The sender had described the consignment as a collection sensors, manufactured in Denmark, that assist people in parking their cars.
A customs check revealed that the five sets of devices were designed to compromise radar signals emitted by police speed guns.
Each set included a control box and four sensors plus other accessories.
Police radar guns determine a vehicle's speed by measuring the difference between the frequency of an emitted signal and the frequency of a signal that bounces back from targeted vehicles.
Devices that scramble those signals are banned from export and import under Vietnamese government regulations.
Their investigation remains underway.