According to the official New China News Agency, the soldiers acted only after they were attacked by the refugees. But according to the New York Times,
The long-range video shows a slow, single-file line of Tibetan refugeesThe People’s Republic of China invaded Tibet in 1950 and annexed it in 1958. Tens of thousands of Tibetans died resisting Chinese rule. There is a large exile community of Tibetans including the Dalai Lama.
climbing over a snow-covered mountain pass followed by Chinese troops. A rifle
shot is heard and the first climber in the pack falls to the ground, followed by the climber at the tail end of the group.
A separate shot shows a uniformed Chinese soldier firing a rifle. It then shows several soldiers examining the shooting victims and escorting some
detainees back to a camp.
The video was first shown on Pro TV, a private Romanian network, and was posted on the Internet. It was taken by Sergui Matei, a Romanian cameraman on a climbing expedition on Cho Oyu, a peak near China’s border with Nepal.
FP Passport makes the interesting observations that while the Chinese are concerned about refugees from North Korea entering China on its northern border they are killing refugees on the southern border to prevent them from leaving.