Hackers infiltrated French government computers in search of information about France's leadership of the Group of 20 leading economies. The attack took place late last year and the intruders infiltrated around 150 computers and stole numerous documents, out of a total 170,000 computers in France's Finance Ministry, according to the BBC.

"We noted that a certain amount of the information was redirected to Chinese sites," an anonymous official was quoted by Paris Match magazine, which first broke the story. "But that does not say very much."

Hackers were able to break into the Ministry's computers after e-mailing a malicious Trojan horse to users. This allowed the hackers to access the computers remotely via a backdoor.

Patrick Pailloux, director general of the French National Agency for IT Security, admitted it was not the first time government computers had been attacked but that "it's the first time that it has reached such proportions," he said on radio station France-Info. "It is the first attack of this size and scale against the French state," Pailloux said. He confirmed "sensitive" information had been obtained in the attack, which he said was carried out by "a number of professional, determined and persistent hackers."

Budget Minister Francois Baroin says it's too early to say who was behind the attack though he did say they had leads. In an interview on radio station Europe-1, Baroin said that "it was the information about the G-20 that interested the hackers."

France this year held the rotating leadership of the G-20 in February. The series of meetings was aimed at improving relations among the world's top economies.