China sales at US tech companies could be hit hard by fallout from a US government spying scandal, Reuters reported. Cisco shares tumbled 11% on Thursday, a day after it warned that revenue could drop as much as 10% this quarter, and continue to contract through the middle of next year, in part due to a backlash in China after revelations about US government surveillance programs. “All the big US IT companies are concerned,” said Jim Lewis, a senior fellow with the Center for Strategic Studies in Washington, who is an expert on China and technology. “But so far Cisco is bearing the brunt of it.”