PARIS (AFP) – The French finance ministry has shut down 10,000 computers after a "spectacular" cyber attack from hackers using Internet addresses in China, officials and reports said Monday.

The hackers were hunting for documents relating to the Group of 20 (G20) developed and developing nations, which this year is led by France, said Budget Minister Francois Baron, adding that a probe was under way into the attacks.

"We have leads," Baroin told Europe 1 radio, saying that what he called a "spectacular" attack was "probably the first time" that the French government's computer system had been hit on this scale.

President Nicolas Sarkozy is determined his G20 legacy will be the reform of the world financial and trade system, in order to iron out the imbalances that led to the recent global economic crisis.