One analyst had been disciplined for using NSA resources to track a former partner.

A fascinating and disturbing fact about the NSA.

From time to time, the spy agency's employees abused their power to spy on lovers, according to the Wall street Journal.

The Journal said:

The practice isn't frequent - one official estimated a handful of cases in the last decade - but it's common enough to garner its own spycraft label: LOVEINT.

The LOVEINT violations involved overseas communications, officials said, such as spying on a partner or spouse. In each instance, the employee was punished either with an administrative action or termination.

The NSA, which is at the centre of claims it is abusing power, admitted that some of its analysts had deliberately abused its surveillance systems.

One analyst had been disciplined for using NSA resources to track a former partner.

The NSA said it had found "very rare instances of wilful violations of NSA's authorities".

"NSA takes very seriously allegations of misconduct, and co-operates fully with any investigations - responding as appropriate," the NSA said.

"NSA has zero tolerance for willful violations of the agency's authorities."

Senator Dianne Feinstein, the chairwoman of the Senate intelligence committee said that she had seen no evidence that any of the violations involved the use of NSA's domestic surveillance infrastructure.