Baidu, China\'s biggest internet company by market value, hosted a visit from Politburo member Li Changchun this month as the government steps up monitoring of web services providers. Li was joined in his September 5 visit to Baidu by other Chinese Communist Party officials including Liu Qi, secretary of the Beijing municipal committee, the internet company said in a statement on its website yesterday. The officials were shown technology such as the new homepage of Baidu, owner of China\'s most-popular search engine, according to the statement. China, which exerts control over all traditional media such as television and newspapers, is tightening scrutiny of information on the web as more users gain access, Duncan Clark, chairman of telecommunications consultants BDA China, said. Sina, operator of the Twitter-like Weibo microblogging service, was visited by Beijing communist party chief Liu last month. \"If you look at the reach of these internet sites now, they rival or exceed the reach of state media,\" Clark said. \"Any visit by somebody that senior to such a high profile company is a signal, for sure.\" Core values Sina will ensure that the information it provides online is authentic, and is committed to the spread of ‘the core values of socialism,\' the Shanghai-based company said on September 9. Liu asked websites to strengthen management and eliminate the spread of fake and misleading information on microblogs. Li, a member of China\'s ruling Politburo Standing Committee along with President Hu Jintao and Premier Wen Jiabao, supports Baidu\'s domestic and international expansion, the Beijing-based company said. Baidu accounted for 75.9 per cent of China\'s search-engine market by revenue in the second quarter and 75.8 per cent in the previous three months, according to Analysys International. Google\'s share dropped to 18.9 per cent from 19.2 per cent, it said. China had 485 million internet users at the end of June, according to data from the government-sponsored China Internet Network Information Centre.