Citrix Systems says hackers gained access to its internal network

Networking software company Citrix Systems Inc said on Friday it has taken action to fix incident involving unauthorized access, possibly by international cyber criminals, to its internal network.

Citrix also said it was contacted by the US Federal Bureau of Investigation on Wednesday regarding the incident.

Shares of the company fell about 3 percent to $99.86 in noon trading.

"We commenced a forensic investigation; engaged a leading cyber security firm to assist; took actions to secure our internal network; and continue to cooperate with the FBI," the company said in a statement.

Citrix, however, did not mention the specific documents that may have been accessed by the hackers.