[Today, we have received confirmation that the web site tibet.org cannot be accessed in China. TS]

BEIJING, Sept 12 (Reuter) - A Chinese government spokesman said on Thursday he was unaware of political censorship on the internet but management of the computer network by the state was normal.

Asked about reports of growing efforts by Beijing to block access to sensitive sites on the internet's World Wide Web, Foreign Ministry spokesman Shen Guofang said that techniques for managing the global network were constantly being updated.

"Every country has some management of the (computer) network and the methods are constantly being updated and changed," he told reporters. "It should be said this is relatively normal."

Network users have said that Beijing was stepping up domestic controls on sensitive sites such as those of dissident groups and Tibetans on the Internet's World Wide Web.

"We have the ability to control them," said an official of the Ministry of Posts and Telecommunications who declined to be identified. "We have measure to protect our nation's security."

Industry experts put the number of signed-up Internet users in China at around 100,000, but say the sheer pace of growth make reliable statistics hard to come by.