Cybersecurity and Infrastructure Security Agency

In the warning issued on Wednesday, which came from several countries, it was revealed that Chinese cyber espionage was aimed at military and government organizations in the US, Reuters reported.
The Chinese government has rejected claims it is spying on Western targets, calling the warning from the US and its allies a "collective disinformation campaign".

Perpetrator still unknown

The attacks of August 22 last year compromised a string of public services, including the websites of the government and the Revenue and Customs Administration.

According to the Ministry of Public Administration, 17 "information systems" in 10 institutions were infected, with 150 computer directly affected.

Fake emails purportedly from the US Department of Homeland Security warning of cyberattacks were sent out on Nov. 13 from a secure FBI computer server, computer security experts said.

U.S. intelligence and law enforcement agencies said on Jan. 5 that Russia was probably behind the massive SolarWinds hack that has shaken government and corporate security, contradicting President Donald Trump, who had suggested China could be to blame.

The US energy department is the latest agency to confirm it has been breached in what is being described as the worst-ever hack on the US government.

 The department is responsible for managing US nuclear weapons, but said the arsenal's security had not been compromised.

Hackers believed to be working for Russia have been monitoring internal email traffic at the U.S. Treasury and Commerce departments, according to people familiar with the matter, adding they feared the hacks uncovered so far may be the tip of the iceberg.