From Google Blogoscoped:

Many Chinese are currently reportedly angered at France for an attack against a wheelchair-bound Olympic torch bearer that took place in France, as well as Paris awarding honorary citizenship to the current Dalai Lama of the Tibetan Buddhists… so some people in China wanted to boycott French hypermarket chain Carrefour. And now, a search for 家乐福 (Carrefour) in Google.cn does not show any of the 6+ million results it shows in Google.com – instead, Google China returns a nearly blank page with a single message that (if an automatic translation is to be believed) roughly means, “You cannot access information of this search result, please return to google.cn for other information.” While censorship of selected domains is common for Google China, keyword-based censorship is more rarely to be seen. Plus, this specific filter covers not only web search but other services, like news or video search, as well.

Read also Carrefour now a sensitive word by Joel Martinsen, and Is it Google or China censoring Carrefour? by Garett Rogers.

Also, from Beijing Times, via Sina Financial News :

The Internet Monitoring Department of the Beijing Public Security Bureau said “Carrefour” is filtered at the search engine level.

According to the explanation of on-duty personell at the Public Information Network Security Monitoring Department of Public Security Bureau of Beijing, the reason for blocking “Carrefour” is that related search results relate heavily to “Sino-French relations” and “Tibet Independence”. They likely contain contents which violate relevant laws and regulations.

Beijing-based technology blogger Keso commented this news on his blog, translated by CDT:

This is probably the first time the Internet Monitoring Department admitted they played a role in search results of certain keywords, thanks to Beijing Times. But I think it is far from sufficient to just filter out one “Carrefour” word; words such as “China”, “people”, “Olympics” and “Beijing” all can produce search results that “likely contain contents which violate relevant laws and regulations.” Let me put this way: Internet users search any combination of 27484 Chinese characters, or even search any English words combining any 26 letters, and they all “likely contain contents which violates relevant laws and regulations.” Therefore, all words should be filtered. Why just “Carrefour”? So unfair.