One of Uganda's best-known mountain gorillas, Rafiki, has been killed.

Four men have been arrested, and they face a life sentence or a fine of US $5.4 million if found guilty of killing an endangered species.

Investigations showed that Rafiki was killed by a sharp object that penetrated his internal organs.

There are just over 1,000 mountain gorillas in existence and the Uganda Wildlife Authority described Rafiki's death as a "very big blow".

The silverback, believed to be around 25-years-old when he died in the Bwindi Impenetrable National Park, was the leader of a group of 17 mountain gorillas.

[Source: BBC]