Although Twitter has been blocked in China since it was used to spread images and messages of deadly Uyghur riots in Xinjiang in July 2009, millions of Chinese Internet users have found a way around the blockage. They have their own version of Twitter, called microblogs, which are offered by China's major Internet portals. Indications are that while the authorities are nervous about the messages, which can be 140 characters long, and have shut down some threads, mostly they have left them alone. Internet users can repost the threads after they have been censored, and the followers of that tweet can forward the post within a second, creating a huge Internet traffic.