US Navy said there was no evidence the attempt had been successful

It came just a day before decision on China's South China Sea expansion

Chinese hackers tried to steal information from a US aircraft carrier patrolling in the South China Sea when the country was under pressure to withdraw its claim over the waters.

USS Ronald Reagan, a nuclear-powered aircraft carrier, was on patrol in July when a Chinese-based group launched the cyber-attack.

A communication containing malware was sent to personnel onboard the vessel impersonated an official message on July 11. It was the day before China's expansionist claims over the South China Sea were dismissed at The Hague.

USS Ronald Reagan, a nuclear-powered aircraft carrier, was on patrol in July when a Chinese-based group launched the cyber attack

The Enfal malware was intended to infiltrate the Nimitz-class aircraft carrier security systems and steal information on military manoeuvres and policy issues.

FireEye, a US cyber security business, claims the China-based group behind the attack has in the past tried to compromise other US and Vietnamese defence systems.

A US Navy official there was no evidence the cyber attack had been successful.

Although there are fears cyber-attacks have increased in recent months because of the battle for territory in the South China Sea, there is no reason to believe the July 11 attempt is linked with the Chinese government

Bryce Boland, FireEye's Asia-Pacific chief technology officer, told The Financial Times: 'Many governments and militaries in Southeast Asia lack cyber security controls that can effectively match these elevated threats.

Although there are fears cyber attacks have increased in recent months because of the battle for territory in the South China Sea (Woody Island in the South China Sea pictured)

'For example, personal webmail and unmanaged devices aren't unusual, and many organisations lack the technology to detect unique attacks which haven't been seen before.'

The USS Ronald Reagan's patrols in the area were intended to 'maintain the seas open for all to use'.