A white-hat security company has uncovered more evidence that may indicate the Chinese government was behind the vast cyberattack that knocked offline GitHub and a Chinese-language edition of the New York Times. The malicious code used to launch the attack originated with China Unicom, the state-owned telecommunications company that's helped Beijing block content in the past, according Errata Security CEO Rob Graham.

Graham published a blog post late Wednesday describing how he manipulated the technical details behind his Web request to identify the server where a request is being interrupted. Some investigation revealed that IP addresses belonging to computers at China Unicom were responsible.

“While many explanations are possible, such as hackers breaking into these machines, the overwhelmingly most-likely suspect for the source of the GitHub attacks is the Chinese government,” he said.

The new evidence came just days after GitHub, which hosts the anti-censorship organization GreatFire.org, and CN-NYTimes were knocked offline by a distributed denial of service (DDoS) attack. A DDoS attack essentially blocks a site by overwhelming it with traffic. The hack also coincides with a new executive order from U.S. President Barack Obama that gives the U.S. the ability to impose economic sanctions on any one person or organization deemed responsible for launching a cyberattack on U.S. interests.