The shooting happened Sunday following a manhunt for three suspected members of a "violent terror group" linked to a 2015 attack in Pishan county, according to the regional government's official Tianshan website.
No details were given about the attack two years ago.
The killing came less than two weeks after three "rioters" were shot dead for allegedly attacking a Communist Party office in Xinjiang.
China tends to reserve the "terror" or "terrorist" label for attacks involving the mostly Muslim Uighur ethnic minority.
The far-western region is the homeland of the Uighurs -- many of whom complain of discrimination and controls on their culture and religion -- and is often hit by deadly unrest.
Beijing regularly accuses what it says are exiled Uighur separatist groups such as the East Turkestan Islamic Movement of being behind attacks in the resource-rich region.
But overseas experts doubt the strength of the groups and their links to global terrorism, with some saying China exaggerates the threat to justify tough security measures.
In November 2015, police killed 28 members of a "terrorist group" over the course of a 56-day manhunt following an attack on a colliery in Xinjiang's Aksu region two months earlier that left 16 people dead.
In March 2014, 31 people were knifed to death at a train station in Kunming, in southwestern China, with four attackers killed, with Xinjiang separatists blamed and state media dubbing it "China's 9/11".
Two months later 39 people were killed in a bloody market attack in Urumqi, the capital of Xinjiang.
Published : January 09, 2017
By : Agence France-Presse