Members of Congress blasted four U.S. tech giants Thursday, accusing the companies of willingly helping China oppress internal dissent in return for access to a booming Internet market.

Representatives from Microsoft Corp., Yahoo Inc., Cisco Systems Inc. and Google Inc. defended themselves at a House International Relations subcommittee hearing, but a Google official acknowledged that figuring out China's Internet market "has been a difficult exercise."

But lawmakers were skeptical of what several saw as the companies' efforts to explain their business practices in China only after a recent crush of negative media scrutiny and government attention.

Get Breaking News Delivered to Your Inbox

Rep. Tom Lantos, ranking Democrat on the International Relations Committee, told the company officials that they had amassed great wealth and influence "but apparently very little social responsibility."

"Your abhorrent actions in China are a disgrace," the Californian said. "I simply don't understand how your corporate leadership sleeps at night."

The companies, in prepared testimony, appealed for guidance on how to work in what they called a challenging marketplace.

Google's Elliot Schrage said "the requirements of doing business in China include self-censorship — something that runs counter to Google's most basic values and commitments as a company."

Still, he said, Google decided to enter China because it thought it "will make a meaningful, though imperfect, contribution to the overall expansion of access to information in China."

Yahoo's Michael Callahan testified that "these issues are larger than any one company, or any one industry."

"We appeal to the U.S. government to do all it can to help us provide beneficial services to Chinese citizens lawfully and in a way consistent with our shared values," he said.

James Keith, senior State Department adviser on East Asian affairs, told lawmakers that China's efforts to manipulate the Internet have increased in the last year, "sending a chilling message to Internet users."

China's "effort to regulate the political and religious content of the Internet is counter to our interest, to international standards and, we argue, to China's own long-term modernization goals," Keith said in prepared testimony.

