The Chinese authorities have claimed that recent disruptions to local internet services can be traced to overseas actors, despite suggestions to the contrary.
The country was recently accused of affecting traffic between citizens and US services, but has always claimed that it is the frequent target and the regular victim.
But local news source China Daily reported on information released by the Chinese equivalent of CERT, the National Computer Network Emergency Response Technical Team Coordination Centre, that said China itself has been targeted by hackers.
Chinese users complained on Friday that attempts to visit sites including cnn.com and yahoo.co.jp were being redirected to travel site ptraveler.com, which is currently showing a '500 error' page.
An insider at the Chinese CERT told China Daily that the attack was unusual and employed a unique method.
"It was a rather strange case because the hackers were directly targeting the telecom carriers' servers. It has rarely happened before," said the source.
"China Telecom was the biggest victim because it is the largest internet service provider. It is impossible to estimate the damage at the moment."
The Centre said that, while China has a relatively resilient security curtain, it is frequently attacked and is showing signs of weakness.
Earlier this week the Chinese government criticised state security moves in the US by the Pentagon, and the apparent accusatory approach it takes to China.
"We are following the new US cyber security strategy and concerned about it. The report makes groundless accusations about China, and we resolutely oppose it," said Chinese defence ministry spokesman Geng Yansheng earlier this week.
This is not the first time that Chinese citizens have been prevented from accessing such services. Earlier this year the censorship group Greatfire.org traced a denial-of-service attack on GitHub to the Chinese government.
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