The Middelburg K9 Unit spotted a suspect Toyota Quantum on the highway and after bringing the vehicle to a halt, conducted a spot search.
When the engine bonnet was opened, K9 members discovered two large object wrapped in plastic.
Upon closer inspection, the two horns were discovered.
The driver, whose identity is known to Middelburg Observer, but who has not appeared in court, was arrested and booked into custody on charges of possession of rhino horns.
The horns are estimated to be worth R8 million on the black market.
The driver alleged that he is from Mbombela.
On the scene he told arresting officers that the horns were poached in the Kruger National Park two days ago.
KNP Communications Manager Mr Reynold Thakhuli told Middelburg Observer that the park has not been notified of either the arrest, nor the allegations made by the suspect.
He says that the park is not aware of any poaching incident the past two days, but that an investigation will be launched.
The park is part of the specialized anti rhino poaching joint-ops, which include specialist prosecutors and court.
The 42-year old suspect is expected to appear in court by latest Friday.
DNA testing will be done on the horns in order to trace their origin.
Highly organized poaching and smuggling syndicates are believed to be involved.