US presidential candidate Hillary Clinton has accused China of "trying to hack into everything that doesn't move in America" and stealing government information, in strongly worded comments likely to irk Beijing.
Clinton, a former secretary of state, pulled no punches in remarks to Democratic supporters at a campaign event in New Hampshire on Saturday.
President Barack Obama said the U.S. is confronting national security threats from violent extremism to Russian aggression that will take years to resolve.
The president’s approach is described in his National Security Strategy, a 33-page document to be released on Friday that offers a counterpoint to Republicans who say Obama has been too slow and timid in confronting global challenges.
The US is lobbing fresh sanctions against North Korea as a response to the cyber attack on Sony Pictures Entertainment even as President Barack Obama's administration refuses to provide evidence of Pyongyang's involvement.
China may have the ability to remotely shut down computer systems of US power utilities, aviation networks and financial companies, according to director of the US National Security Agency Mike Rogers.
Testifying to the House of Representatives Intelligence Committee on cyber threats, Rogers said digital attackers have been able to penetrate such systems and perform "reconnaissance" missions to determine how the networks are put together.
Chinese hackers have attacked the US weather satellite network, causing services to be sealed off for a period.
The US regularly accuses China of state sponsored assaults on its businesses, industries and utilities.
The US is currently talking of a cooling in trade hostilities that would ensure the smooth passage of technology sales, but the cyber attack allegations still keep coming. The Washington Post reported that the weather satellite attacks happened in September, but were not revealed until late October.