'Secret Pentagon papers' show China hacked into Patriot missile system

Chinese spies have allegedly hacked into the designs of many of the United States' advanced weapons systems and platforms, including those for F/A-18 Hornet fighter jets, the Patriot missile system and Black Hawk helicopters.
According to the Washington Post, a "confidential section" of a report prepared for the Pentagon seen by the paper makes the claims. The confidential section alleges that 25 of these hacked designs were in programmes critical to American missile defences, combat aircraft and ships.

The Defence Science Board has already warned in the public part of the report (PDF), released in January, that the Pentagon wouldn't be able to defend itself in the event of a full-scale cyber-conflict.

"After conducting an 18-month study, this Task Force concluded that the cyber threat is serious and that the United States cannot be confident that our critical Information Technology (IT) systems will work under attack from a sophisticated and well-resourced opponent utilising cyber capabilities in combination with all of their military and intelligence capabilities (a 'full spectrum' adversary)," the report said.
However, the report also included a confidential list of compromised weapons, which included the US Army's system for shooting down ballistic missiles, the Terminal High Altitude Area Defence, and the US Navy's Aegis Combat System, also designed to defend against ballistic missiles.
According to the WP, sensitive design information for aircraft and ships was also illicitly accessed, including: the V-22 Osprey tiltrotor transport aircraft; the US Navy's new Littoral Combat Ship, designed to patrol close to shore; and the F-35 Joint Strike Fighter, which the UK is procuring to fly from its two new Queen Elizabeth-class aircraft carriers.
The Defence Science Board didn't claim that Chinese agents were behind the cyber attacks, but top military and industry sources who knew about the breaches told the paper that the hacks were part of a growing Chinese campaign of espionage.
The US has been increasingly vocal about what it claims is increased espionage by the Chinese government and Chinese-controlled corporations. The White House has made it clear that cyber-security is a top concern, and has accused both China's government and Chinese companies of continuous attacks aimed at stealing intellectual property.
China has consistently denied any charges of cyber-snooping on American agencies or companies and has flung back accusations against the US government, claiming that it is using cyber-espionage techniques against China