The attack was aimed to sabotage the Beijing Games.
An unidentified spokesman of the Xinjiang regional department of public security said some people used "a number of telephones outside the country" to direct mobs in Xinjiang to stage the violence.
Twitter is increasingly popular in China, but its user base is confined mostly to well-off urbanites.
Residents walk past a smashed up shop front following riots in Urumqi, western China's Xinjiang province, Monday, July 6,
Yet in China, where a computer-savvy youth has embraced the Internet with enthusiasm, the government has not been able to control all the information seeping out of Xinjiang.
The supermarket, in Houquan street, lost more thanyuanU.
Most resented of all, no one under 18 is allowed to worship or to receive religious instruction.
The Chinese sites were not blocked on Monday afternoon.
Dilxat said some protesters were beaten badly.
Although traffic control was lifted Monday morning in parts of Urumqi and debris has been cleared from the roads, residents were still trembling in fear.
The official death toll from the riots outstrips any unrest in China in many years.
CCTV9 news report in English.