The State Department's computer system has fallen prey to hackers over the past several weeks. Sources say that irregularities were detected on the department's unclassified computer system, but that the classified system was not compromised. Sources also tell ABC News that it appears that these hacking attempts came from East Asia and that they appear to be broader than just an effort by one person, although they could not say how organized that effort was.

ABC News is told that the State Department is still working through an investigation so can't say that no data was lost yet, but that they had no reason to believe at this time that there was any significant loss of data or information.

The irregularities were first detected in mid-June and some of them persisted through early July. State Department spokeswoman Nancy Beck said in a statement that "As an added precaution last week we limited access to secure or encrypted sites such as banking and personal emails." This was done because the State Department feared that personal information such as bank account or password information could have been stolen as a result of the security breaches.

One source points to this as a success of the measures that are employed to monitor the department's network, saying that the problem was detected and dealt with quickly.