A group of fossils discovered in the Qinghai-Tibet Plateau, known as the Roof of the World, have been confirmed as pliocene-era hyenas some four million years ago, a Chinese archaeologist said Wednesday.

The fossilized teeth and lower jaws were found at an altitude of 4,195 meters in the desolate Zanda basin, southwest of Tibet Autonomous Region in southwest China, back in 2012.

After years of research by China and the United States, both sides are in agreement that the fossils date from the pliocene age, and the discovery is the first found on the Qinghai-Tibet Plateau, according to the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) under the Chinese Academy of Sciences.

This proves that hyenas lived on the plateau, and as far as in west Europe, during early Pliocene Epoch (five million to three million years ago), said Li Qiang, an IVPP researcher.

"Pliocene hyenas were dog-like predators. Their bone-crushing teeth were perfect for tearing up prey," said Li.

Pliocene hyenas belong to the Hyaenidae family, which first appeared during the late Miocene Epoch (11.6 million to 5.3 million years ago), said Li.