The Chinese government has cut off internet service and blocked access to Twitter in a region of the country, after deadly riots left 140 people dead in a remote northwest region of the country.

Chinese media reports indicate 140 people have been killed in the Xinjiang Urumqi Autonomous region, and a total of around 800 people -- with that number still climbing -- have been injured.  Chinese search engines no longer yield any search results when Chinese internet users search for "Urumqi."

Residents of the city say internet has been completely cut off in Urumqi, and they have not been told when it will be restored.

Now that the protests reportedly have spread outside of Urumqi, it's possible others will face internet crackdowns later this week.  

In addition to internet restrictions and a crackdown on Twitter, YouTube also has been temporarily blocked by the government, which is attempting to create a certain level of damage control.  The internet will reportedly remain off to help stifle the spread of the riots, but official word from the Chinese government isn't expected to discuss the recent internet shutoff.

The Chinese government is well known for cracking down on internet users after similar events, and also closely controls what kind of content can be seen by internet users.  The government has drawn criticism from some PC manufacturers and security experts over its Green Dam filtering software that must be installed on all PCs and laptops sold in the country.

Despite the power of the Great Firewall of China, many internet users are able to find ways around the firewall so they are able to still read any content they like.  These freedoms, including the use of social networking sites and YouTube, is the reason the Chinese government also is cracking down on Twitter and YouTube.