Chinese and Russian military forces are engaged in joint exercises in northwestern China as ties grow between the two autocratic states amid uncertainty over instability in Afghanistan.

       The exercises involving ground troops and air forces are due to continue through Friday in the Ningxia Hui Autonomous region.

       The region borders on Xinjiang, where China has detained more than 1 million Uyghurs and members of other Muslim minorities in what it calls a campaign against terrorism and extremism.

       Xinjiang shares a narrow frontier with Afghanistan, and Beijing is concerned about violence spilling over its border if the Taliban take control in the country following the pullout of U.S. troops.

       While not part of a formal alliance, Russia and China have aligned their military and foreign policies largely in opposition to those of the U.S. and its allies.

       The official Xinhua News Agency said the exercises began Monday and were presided over by Li Zuocheng, a member of the ruling Communist Party’s Central Military Commission.

       The exercise aims to “deepen the joint anti-terrorism operations between the Chinese and Russian militaries and demonstrate the firm determination and strength of the two countries to jointly safeguard international and regional security and stability,” Xinhua said, citing Chinese and Russian officials.

       “It reflects the new height of the China-Russia comprehensive strategic partnership of coordination for a new era and of the strategic mutual trust, pragmatic exchanges and coordination between the two countries,” Xinhua said.

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