A 9-year-old girl died late Monday from head injuries sustained in a school stampede in northwest China's Xinjiang Uygur Autonomous Region, police said Tuesday.

Sun Manling, a third-grader at the primary school affiliated to Bayi High School in the heart of the regional capital, Urumqi, also suffered injuries to the face, neck and back in the stampede, which occurred at 9:30 a.m. Monday, the city's public security bureau said in a press release.

It said three other students were injured in the accident, including two boys and a girl, all aged 10.

School authorities had mobilized all students from the third to fifth grades to help clean the campus Monday morning, after two days of heavy snow.

"The stampede happened when hundreds of students swarmed towards a storeroom for brooms and spades at the end of a 1.5-meter wide lane," the document said. "One of the them stumbled, causing dozens to fall on top of one another."

It said Sun was a native of Urumqi and both her parents were doctors.

Her parents and teachers were not available for interview Tuesday.

A doctor with Jiangong Hospital said she was in a coma, with no signs of breathing or heartbeat, when her teachers carried her to the hospital Monday. "Her heart beat resumed after artificial respiration, but she never woke up."

He said Sun died towards midnight.

The three injured students suffered slight injuries and were in stable condition, the doctor said on condition of anonymity.

He said two of them were still in hospital Tuesday and the other had gone home with a plaster cast on his injured knee.

Police are still investigating the causes of the accident.

A similar school stampede killed eight students and injured 26 in central China's Hunan Province on Dec. 8, when the students simultaneously tried to exit down a single narrow stairwell after their evening study session.