The riot in the Gannan Tibetan Autonomous Prefecture of Gansu Province was organized and premeditated, the local government cited eyewitnesses as saying on Sunday.
Rioters bound black signs to their foreheads and arms, holding or raising flags of the so-called Tibetan "government-in-exile".
The riot in Gannan saw 94 people injured, with an economic loss of 230 million yuan (32.6 million U.S. dollars), according to local government officials.
Mobsters held a number of the flags when attacking government buildings in the Xiahe County seat on March 15. They raised the flags in government offices and primary schools in Amuquhu Town of Xiahe County on March 17, in Maai Town of Luqu County and Kecai Town of Xiahe County on March 19.
The injured people include 64 police, 27 armed police, two government officials and one civilian. Among the injured, six police and four armed police were in dangerous condition in hospital.
Since March 14, beating, smashing, looting and arson occurred in the counties of Xiahe, Maqu, Luqu and Jone and Hezuo City in the Gannan Tibetan Autonomous Prefecture and the Aba County of Sichuan Province.
The Maqu county was one of the worst hit during the Gannan riot between March 14-19, according to Mao Shengwu, acting governor of the Gannan prefectural government.
Nearly all the shops in a street in Maqu were smashed, and many of them were torched. The street was covered with bricks, stones and glass fragments.
In the county seat of Xiahe, windows were broken. In Amuquhu town, Xiahe, not only windows of the local government, police bureau, health center and judiciary office were broken, but also trees in the police bureau were chopped down and televisions smashed.
Social order in Gannan has returned to normal. There has been no fresh unrest since March 20.
At least 18 civilians and one police officer have been confirmed killed in the Lhasa unrest, which also saw 382 injuries. Damage is estimated at more than 244 million yuan.
The casualties and damages from riot in Aba County, Sichuan, are not available yet.