China has accused the United States of hacking into computers at a military research university and frequently collaborates with the state on national security projects.

On Monday, China’s National Computer Virus Emergency Response Center announced that the Northwestern Polytechnical University reported computer break-ins in June.

Foreign Ministry spokeswoman Mao Ning condemned Washington’s actions, saying it “seriously endanger(s) China’s national security,” Ms Ning also accused Washington of eavesdropping on Chinese mobile phones and stealing text messages.

“China strongly condemns it,” Ms Ning said. “The United States should immediately stop using its advantages to steal secrets and attack other countries.”

The centre, collaborating with commercial security provider Qihoo 360 Technology Co., traced the attacks to Washington’s National Security Agency but didn’t say how that was done.

The joint investigation concluded that Trojan attacks that saw nearly 140 gigabytes of data stolen in recent years from China had originated in the United States.

It alleged that Washington stole its data through cyberattacks on networks which controlled “tens of thousands” of devices, ranging from servers to firewalls.

In March, Qihoo released a report saying a hackers’ group named APT-C-40 had affiliated with Washington and had been attacking leading Chinese companies, governments, research institutes and infrastructure in the last ten years.