Budget Minister Francois Baron said an investigation was underway into the origin of the attacks.
'We have leads,' unconfirmed at this stage, Baroin said.
Earlier, the Paris Match magazine said that the management of the French Treasury department was the prime target of the attacks.
The magazine said the hackers were after 'documents related to the French presidency of the G20 and to international economic affairs'.
The actors were determined professionals and organised. It is the first attack of this size and scale against the French state,' the magazine said.
More than 150 ministry computers had been hacked and numerous documents pirated. Individuals were not targetted in the attack.
Other experts said the hack proved targeted attacks against Government organisations have become more commonplace in recent times.
“Often designed to sneak access to sensitive files, the cyber perpetrators are often professionals seeking access to specific pieces of information,” said Mark Darvill, director of security firm AEP Networks, which works with Governments, as well as the military and businesses.
“Without a scaled-up approach to cyber defence, national security is left open to compromise and sensitive information is at the mercy of those who have the technical knowledge to launch these targeted attacks,” he said.
Last month, Foreign Secretary William Hague said the UK Government had been hit by the infamous Zeus Trojan.
Targets were also sent emails containing a link to the Trojan, indicating the attack techniques used against the French and UK Governments were almost identical.
Atlas France Ref. 20197XB 2009, 7e (Michelin France Tourist & Motoring Atlas (spiral))
