Beijing — The Chinese authorities provided new details on Thursday about a violent clash in the Xinjiang region of western China last weekend that they said had left 50 people dead and more than 50 others injured.

According to the government-run Tianshan website, a series of bomb blasts on Sunday killed six people in Luntai County, southwest of the regional capital, Urumqi. Security forces later fatally shot 40 people whom the report described as rioters. Four police officers were also killed, the report said.

“Public security dealt with the situation decisively,” the article said, quoting local police officials. It described the episode as a terrorist attack.

…Rohan Gunaratna, the head of the International Center for Political Violence and Terrorism Research at Nanyang Technological University in Singapore, said much of the recent violence in Xinjiang consisted of spontaneous acts of resistance by disaffected Uighurs. “Beijing has invested in building infrastructure, but not in creating reconciliation,” he said.