At least 129 people have been killed and over 800 injured during riots in China''s Muslim Xinjiang Uygur Autonomous Region, Xinhua said on Monday.

Riots started in the regional capital of Urumqi on Sunday when a group of protesters demanded an investigation into the death of two ethnic Uighurs killed at a fight with Han Chinese workers at a toy factory in late June.

Xinhua said that protesters from the Uighur Muslim ethnic minority group began attacking ethnic Han pedestrians, burning vehicles and attacking buses with batons and rocks.

"They took to the street...carrying knives, wooden batons, bricks and stones," the news agency cited an eyewitness as saying.

The AFP news agency quoted Alim Seytoff, general secretary of the Uighur American Association in Washington, as saying that according to his information, police had begun shooting "indiscriminately" at protesting crowds.

Xinjiang''s eight million Uighurs have complained of political, cultural and religious persecution by Beijing and there have been repeated calls by Uighurs for independence.

Earlier reports said three civilians and a police officer had died in the fighting.