I remember reading about this in the Indian press at the time, didn't realize the video was making the Internet rounds though.
It should be noted that the pilgrims were crossing the border illegally and ignored shouted orders to stop, although of course that doesn't justify the horrific means by which the border guards "handled" it and the video, as well as nearby climbers' eyewitness accounts, make clear that China's claim the soldiers were "attacked" was nonsense. China had been stepping up pressure on Nepal to close offices serving Tibetan refugees in Kathmandu and to more aggressively track down and deport refugees for several months by then, and for years there'd been scattered reports of Chinese border guards firing on (not actually shooting) and illegally pursuing refugees across the border, so sadly the incident did not come as a shock in Nepal. Several of the climbers from the group the man who filmed this was with reported being harassed by Chinese attaches after they returned to their base in Kathmandu--some reported being pressured by trekking company officials (big, big business in that area) not to speak up as well.