The attacks are apparently retaliation for Turkish criticism of China over deadly riots last week, when members of the Uighur ethnic minority clashed with Han Chinese, China's majority ethnic group. The riots in western Xingjiang province left at least 184 people dead and over 1,600 injured, according to the state-run Xinhua news agency.

Turkish Prime Minister Recep Tayyip Erdogan last week called the events "a kind of genocide," and the country's trade minister called for a boycott of Chinese goods. Thousands of Turks reportedly demonstrated in support of Chinese Uighurs over the weekend.

The message left on the defaced Turkish embassy Web site demanded that Turkey not meddle in Xinjiang affairs, which it called China's "internal matter," according to a screenshot on the Web site of China's state-run Global Times newspaper.

China cut off Internet and mobile phone service in Xinjiang after the riots last week to prevent further unrest. It also blocked social Web sites including Twitter and Facebook across the country. Turkish cyber attackers have targeted Chinese Web sites before, though hacking between the countries has not been a hot-button issue.

Most businesses and governments in North America are ill-equipped to repel such assaults, according to Kevin Coleman, senior fellow and chief strategist of the Technolytics Institute, an independent technology and security management think tank based in McMurray, Penn. A co-author of three books Coleman has briefed members of U.S. Congress- both the House and Senate.