Chinese spies have stolen design information about Australia’s new Joint Strike fighter jets, according to secret documents leaked by former US intelligence worker Edward Snowden.

United States National Security Agency documents obtained by German newspaper Der Spiegel show Chinese cyber spies have stolen data relating to the Joint Strike Fighter (JSF) jet.

• Government spends $12.4 billion on fighter jets
• Snowden granted residency

According to Fairfax, the documents, disclosed by Mr Snowden, include details abut the JSF’s radar systems which are used to track targets.

The reports reveal NSA concerns about Chinese cyber-espionage and large volumes of sensitive military information being stolen by spies.

It is understood the breach took place in 2007, years before Prime Minister Tony Abbott placed a $12 billion order for 58 more fighter jets in 2014.

Mr Abbott said the jets would make a “vital contribution” to Australia’s national security.

Tens of thousands of military personnel records were reportedly stolen by Chinese spies, as well as designs for nuclear submarines, stealth bombers and air-defence missiles.

The report also said the US government was preparing for future warfare where the internet will be used to cripple other countries’ economies.

“The Internet will play a critical role,with the aim of being able to use the net to paralyze computer networks and, by doing so, potentially all the infrastructure they control, including power and water supplies, factories, airports or the flow of money,” Der Spiegel reported.