A U.S.-subsidized advocacy group that helps Internet users inside China bypass blockages on censored content says it is suffering a mysterious denial-of-service attack disrupting its operations.
Greatfire.org says the attack started two days ago and Internet traffic is 2,500 times above normal. It says the attack has affected "mirror," or duplicate, websites that it has set up via encrypted web services offered by companies like Amazon.
Greatfire.org said the attack has interfered with visitors to sites with material from news sites including Boxun.com, which publicizes allegations of corruption and human rights abuses inside China; German provider Deutsche Welle, and Google.
The statement from a co-founder of the group, who goes by the pseudonym Charlie Smith, said it's not clear who is behind the attack, but it coincides with increased pressure on the organization over the last few months and public criticism from Chinese authorities.
Zhu Haiquan, spokesman of the Chinese Embassy in Washington, said: "As we have always stated, Chinese laws prohibit cyber crimes of all forms. The Chinese government is making great efforts to combat cyber crimes and safeguard cybersecurity. Jumping to conclusions and making unfounded accusations is not responsible and is counterproductive."
The Chinese government blocks thousands of websites to prevent what it deems politically sensitive information from reaching Chinese users, an effort dubbed the Great Firewall.
According to the free-expression watchdog Freedom House, since late 2013 Greatfire.org has been hosting content on domains owned by Amazon and other major companies, which officials cannot risk censoring because of their large commercial footprint within China.
Smith said the current denial-of-service attack that is flooding the mirror websites is costing the group up to $30,000 per day in bandwidth. He told The Associated Press by phone that Greatfire.org is in contact with Amazon about how to deflect the attack. He said the company has not yet confirmed whether it will forgo the inflated charges.
An Amazon spokesman did not immediately respond to an email seeking comment.
The Open Technology Fund, a U.S.-government-backed initiative to support Internet freedom, says on its website it provided Greatfire.org with $114,000 in 2014.
Greatfire.org says it gets its funding from a variety of sources, including from people and organizations inside China.
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