Local Kunming government officials say that evidence at the scene point to separatists from China’s restive Xinjiang region, in what is being called “an organized, premeditated violent terrorist attack.” China’s state media outlet Xinhua quotes domestic senior Chinese security official Meng Jianzhu as vowing to “severely punish” the attackers “according to law.” Those comments were later echoed by President Xi Jinping, who also heads China’s security commission. The Global Times reports that Xi has asked “law enforcement to crack down on violent terrorist activities in all forms.” It also notes that UN Secretary-General Ban Ki-moon expressed his hope that “those responsible will be brought to justice.”
If Xinjiang wants to govern itself, it has the right to govern itself.
So even if all of Xinjiang unanimously agreed they wanted to secede and govern themselves, China would still have the right to govern them because they want a natural resource they have?
That's called stealing.
Has all of Xinjaing agreed?
Also it's not an easy decision to to let a state which was a part of the nation self govern. Especially if one has developed the said nation for gains. This province (of which I just can't pronounce the name of) has probably seen plenty of resources being allocated to it by the central government.
Also if the separatist were to self govern the country could face security issues in the future.