The International Monetary Fund has revealed it has been the target of a cyber attack on its computer systems.
An IMF spokesman confirmed the attack, which highlights a growing rash of network break-ins at high-profile institutions.
"The fund is fully functional," IMF spokesman David Hawley said.
"I can confirm that we are investigating an incident. I am not in a position to elaborate further on the extent of the cybersecurity incident."
Bloomberg said the IMF's computer system was attacked by hackers "believed to be connected to a foreign government, resulting in the loss of emails and other documents."
The attack occurred before the May 14 arrest of former IMF managing director Dominique Strauss-Kahn on sexual assault charges , it said.
It did not identify a suspect government and cybersecurity experts say it is very difficult to trace a sophisticated cyber break-in to its ultimate source.
Sky News has previously learnt of the growing threat Western governments and corporations under from hackers based in countries such as China.
Experts say the covert action was to install software that would give a nation state a "digital insider presence" on the network, a cybersecurity expert who has worked for the IMF and World Bank said.
"It was a targeted attack," said Tom Kellerman, who understands the network architecture at both international financial institutions and who serves on the board of a group known as the International Cyber Security Protection Alliance.
"The code was developed and released for this purpose," he said.
An official with the World Bank, it sister institution in Washington, said the World Bank had cut its network connection with the IMF out of "caution."
The information shared on that link was "non sensitive info," the official added