Trump was accompanied by security from both the US and Mongolia on the trip, the outlet reported. The argali sheep, with its large horns, is considered a national treasure there, and permission to kill one is “controlled by an opaque permitting system that experts say is mostly based on money, connections and politics”.

In between the killing and the issuing of the permit the month after he left the country, Trump is said to have met with the president, Khaltmaagiin Battulga, suggesting the possibility of special consideration being given to the son of the US president.

“Trump Jr shot his argali at night, using a rifle with a laser sight, the guides said,” according to ProPublica. “He stopped the local hunting guides from dismembering it at the kill site, instead instructing them to use an aluminum sheet to carry the carcass so as not to damage the fur and horns, said Khuandyg Akhbas, 50, one of the guides. He also killed a red deer, which similarly required a permit.

The legality of the importation of big game trophies into the United States has been, like many other issues in the Trump administration, confusing and ever-changing. The president himself has spoken out against the practice, calling such hunting practices a “horror show” despite his two sons being avid trophy hunters.

In order to import trophies of animals on the endangered species list, a US hunter must show that its killing would be beneficial overall to the species at large. In 2017, the Trump administration pushed back against such restrictions on trophy hunting from the Obama era before reinstating the ban. A court ruling found thereafter it was done improperly, allowing imports to continue.