Since the controversial Iranian presidential election last month, social-networking website Twitter has become a powerful source for outsiders attempting to find out what really happened.
In the case of the Xinjiang riot, which broke out in Urumqi on Sunday, overseas media also used pictures posted by netizens on Twitter.
However, not all the information was correct. On Monday, Reuters used a picture posted on Twitter that day purportedly taken during the Urumqi riots.
The picture, showing lines of paramilitary officers in a standoff with protesters, was actually taken during a riot in Shishou , Hubei , late last month.
It was published by the Southern Metropolis Weekly on June 26 with a caption saying it was taken in Shishou on June 21.
The picture was carried by the website of British newspaper The Daily Telegraph on Monday and caused a buzz among Chinese netizens. It was removed yesterday.
Similar slip-ups during the riots in Tibet in March last year gave Beijing an opportunity to discredit western media.
German RTL television had to apologise after it used a picture showing Tibetan monks protesting in Nepal and said it had been taken in Lhasa. CNN was also accused of doctoring a Tibetan riot picture. Xinhua said the picture, which showed people running in front of a military truck, had been cropped. The original photograph also showed mobs throwing stones at the truck.
That is probably why the caption of a picture that appeared on the website of British newspaper The Guardian caused an uproar among netizens last night.
The picture showed a four-year-old Uygur girl in Urumqi receiving treatment in a hospital. The caption said her pregnant mother had been shot. Many netizens have questioned the caption, as so far there have been no witness reports that shots had been fired.