Gehlen's longtime chief of counterintelligence had been working for Moscow all along.

Those alleged contacts are among the topics of the FBI counterintelligence investigation.

Three hundred FBI agents have been assigned to counterintelligence duty in NYC.

For instance, utterly ruthless counterintelligence against corruption, or horrendous evils like paedophilia.

One handwritten note from the FBI's then-director of counterintelligence said: What's our goal?

But it is the FBI's job to investigate counterintelligence, Rubio said.

Roseanne eventually left the unit for the Washington Field Office and foreign counterintelligence.

The use of informants is commonplace in counterintelligence and criminal investigations.

For the next six years Cooper remained in the counterintelligence division.

This was as much a counterintelligence investigation as a criminal one.

And this counterintelligence is for the purpose of frustrating your adversary.

The investigation collapsed and the counterintelligence nightmare confronting the CIA grew under Webster.

Angleton was promoted to chief of counterintelligence when it was over.

During his FBI career, Strzok rose to deputy assistant director, focusing on counterintelligence.

And now it's a nightmare for the counterintelligence guy to find them all.

Helms met with the agency's barons, including James Angleton, chief of counterintelligence since 1954.