Johannesburg: Two men have been arrested in connection with the theft of rhino horns worth about $5.2 million from a South African game park office, the Hawks criminal investigation unit said on Monday.

Thieves broke into the Mpumalanga Tourism and Parks Agency south-east of Johannesburg in April and cut into a strong box, making off with 112 pieces of rhino horn, weighing 80 kilograms, in the first known theft of its kind.

“We have arrested two people and they will be appearing in court today,” Captain Paul Ramaloko from the Hawks said, adding that the horns had not yet been recovered.

Most of the horns stolen from the park were from de-horning operations, which is an attempt by local authorities to decrease poaching and to protect the rhino species.

The biggest market for illegal rhino horn in recent years has been Vietnam, where the product is sold in pharmacies and over the Internet at about $65,000 a kilogram, making it more expensive than gold, platinum and cocaine.

Ramaloko said he expects to make more arrests related to the theft as the investigation continue.