HONG KONG >> Google withdrew from China eight years ago to protest the country’s censorship and online hacking. Now the internet giant is working on a censored search engine for China that will filter websites and search terms that are blacklisted by the Chinese government, according to two people with knowledge of the plans.

Google has teams of engineers working on a search app that restricts content banned by Beijing, said the people, who asked for anonymity because they were not permitted to speak publicly about the project. The company has demonstrated the service to Chinese government officials, they added.

Yet the existence of the project does not mean Google’s return to China is imminent, the people cautioned. Google often builds and tests different services that never become publicly available.

Google’s reversal in China is the latest example of how American tech companies are trying to tailor their products to enter the massive Chinese market, even if it means tamping down on free speech. LinkedIn censors content in China, for example. And Facebook developed software to suppress certain posts from appearing on the social network, with the aim of potentially deploying it in China, though there was no indication it was ultimately offered to Chinese authorities.

Many of these overtures ultimately appear to fall short of winning over Beijing. Last month, Facebook briefly gained approval to open a subsidiary in China’s Zhejiang province, but that approval was abruptly withdrawn after a matter of hours.

Google’s work on a censored search engine for China has caused an outcry among human rights activists. Many are concerned the company would block a long list of foreign websites including Facebook, Twitter and The New York Times, as well as Chinese search queries including the 1989 Tiananmen massacre and information about the Chinese leadership.

The work may also be unpopular among Google’s own employees.

Although Google pulled its search engine out of China in 2010, the company has lately displayed more interest in regaining access to the world’s largest internet population. In June, Google announced a $550 million investment in the Chinese online retailer JD.com. Last year, Google unveiled plans to open a research center in China focused on artificial intelligence. And the company has released translation and file management apps for the Chinese market. Google now has more than 700 employees in China.