Who is hijacking Chinese Internet traffic and redirecting it to Baidu, the leading Chinese search engine?

Google on Thursday acknowledged that its Chinese users were being redirected to other Web sites but offered no insight into whether the Chinese government -- which exercises tight control over the Internet in China -- might be responsible or why such redirection might be occurring.

"We've had numerous reports that Google.cn and other search engines have been blocked in China and traffic redirected to other sites," said a Google spokesperson in an e-mail. "While this is clearly unfortunate, we've seen this happen before and are confident that service will be restored to our users in the very near future."

It's possible the incident, or some portion of it, could be the result of malware, which often alters critical files in order to redirect Web traffic.

But Philipp Lenssen, who maintains Google Blogscoped, reports the problem goes beyond Google. He said that sites with the word "search" in their domain name -- search.live.com, search.yahoo.com, blogsearch.google.cn, and even www.search.ibm.com.cn -- were all being redirected to Chinese search engine Baidu as of about 1 a.m. Beijing time Wednesday.

And as Danny Sullivan at Search Engine Land points out, a 2002 Reuters article documents China's previous use of Internet traffic redirection as a means of retaliation against Google.

Why would China do such a thing? This week's Chinese Communist Party Congress might be one reason. The event, held once every five years, is typically a time of heightened government sensitivity.

It's also widely known that China is displeased with the Dalai Lama's warm reception in Washington this week. China on Thursday summoned the U.S. ambassador in Beijing and lodged an official protest.

Possibly adding to Beijing's ire, Google's YouTube on Thursday launched a local site in Taiwan, Youtube.com.tw. Like Tibet, China considers Taiwan to be part of China.

A State Department spokesperson couldn't immediately comment on whether the United States saw China's hand behind these Internet traffic problems.