US lawmakers on Friday renewed their call for sanctions against China's top official in the Xinjiang region on the anniversary of riots that left nearly 200 dead. China cracked down hard after the July 5, 2009 rampage in Urumqi, the region’s capital.

Around one million Uighurs or members of other mostly Muslim, Turkic-speaking communities have been detained in a vast network of camps in the name of counterterrorism. More than 40 US lawmakers across the political spectrum on April 3 called on the Trump administration to slap sanctions on Chen Quanguo, the Communist Party secretary in Xinjiang.

But the chairs of the Congressional-Executive Commission on China said the administration has not yet responded to the letter.

"On this sad anniversary, we reiterate that call to hold Chinese officials accountable," said the chairs, Republican Senator Marco Rubio and Democratic Representative Jim McGovern. The Trump administration has repeatedly denounced China's treatment of Uighurs, with Secretary of State Mike Pompeo likening the mass detention to Nazi-era concentration camps.