evidence: During a recent trip along the Tajikistan-Afghanistan border, The Post saw one of the military compounds and encountered a group of uniformed Chinese troops shopping in a Tajik town, the nearest market to their base. They bore the collar insignia of a unit from Xinjiang, the Chinese territory where authorities have detained an estimated 1 million Uighurs, a mostly Muslim ethnic minority. [...] In a statement, Tajikistan’s Foreign Ministry said there are "no People’s Republic of China military bases on the territory of the Republic of Tajikistan," nor "any talks whatsoever" to establish one. [...] Beijing’s moves have been similarly opaque in the rugged mountains spanning Tajikistan, Afghanistan, Pakistan and China: the same chessboard where czarist Russia and the British Empire vied for influence 150 years ago.