A man, surnamed Ma, who is suspected of involvement in the killing of a wildlife protection hero 26 years ago was arrested recently through the joint efforts of police in Qinghai province and the Xinjiang Uygur autonomous region.

The victim, Sonam Darje, was fatally shot by a poacher in 1994 as his team was escorting a group of detained poachers in the Hol Xil Reserve.

The reserve, with an average altitude of more than 4,600 meters in the hinterlands of the Qinghai-Tibet Plateau, is a UNESCO World Heritage site known for its natural beauty and biodiversity. It has the highest altitude and the most diverse population of wild animals of any reserve in China.

In the late 20th century, poachers invaded remote areas of Hol Xil to kill Tibetan antelopes for their fine cashmere, which was in demand for luxury clothing such as scarves.

Because of the poaching, the population of the rare antelope species declined sharply from an estimated 200,000 to fewer than 20,000.

To help protect the antelope, Sonam Darje established an ecological conservation institute in his home county of Zhidoi. He trekked into the backcountry of the reserve a dozen times for field surveys and patrols. He established China's first armed anti-poaching team and ferreted out eight gangs.

On the night of Jan 18, 1994, when Sonam Darje and his four team members were escorting 20 poachers after capturing seven vehicles carrying 1,800 Tibetan antelope hides, Sonam Darje was attacked and killed by the prisoners.

Multiple suspects escaped, but across two decades the Yushu prefectural police never gave up the investigation.

In December 2018, Sonam Darje, who was born in 1954 in Qinghai's Yushu Tibetan autonomous prefecture, was named a "reform pioneer" by Chinese officials.