BEIJING — A powerful arm of China’s government said Wednesday that it had created a new central agency to regulate every corner of the nation’s vast Internet community, a move that appeared to complement a continuing crackdown on political dissidents and other social critics.

But the vaguely worded announcement left unclear whether the new agency, the State Internet Information Office, would in fact supersede a welter of ministries and other government offices that already claim jurisdiction over parts of cyberspace.

China’s State Council Information Office said it was transferring its own staff of Internet regulators to the new agency, which would operate under its jurisdiction. Among many other duties, the agency will direct “online content management;” supervise online gaming, video and publications; promote major news Web sites; and oversee online government propaganda. The agency will also have authority to investigate and punish violators of online content rules, and it will oversee the huge telecommunications companies that provide access for Internet users and content providers alike.

The State Council is a cabinetlike agency that effectively manages the government’s day-to-day operations. Two former officials at its Information Office will run the new agency, and executives from two central ministries — public security and information technology — will also serve in senior positions, the announcement stated.