The FBI agent crucial to the probe against former CIA director David Petraeus is at the center of an internal investigation and media scrutiny.

FBI agent Frederick Humphries is being investigated for improperly handling the Petraeus case. Agents looking into the case found a shirtless photo of Humphries that was sent to a woman involved in the case that has been revealed to the public.

The 47-year-old agent is being investigated for possible inappropriate activities with Jill Kelley who allegedly received threatening emails from Paula Broadwell, Petraeus' biographer and mistress.

An investigation into the agent's relationship with Kelley found that he had sent her a shirtless photo of himself. The picture was sent around six months before Kelley started receiving the emails from Broadwell. Humphries said that the two did not have a relationship and is quoted in the Seattle Times as saying it "was a tongue-in-cheek joke."

The photo, taken at MacDill Air Force Base, shows Humphries posed between a pair of target dummies that resemble the agent. The caption on the photo reads, "Which One's Fred?"

Humphries supposedly did not look further into Kelley's email troubles and an investigation by other agents discovered the photo while looking through her emails.

The agent is criticized for his handling of the Petraeus case which even he said was flawed. Humphries went to Congressional representatives in October to complain about the investigation.

Humphries however has the support of Jon Adler, president of the Federal Law Enforcement Officers Association, who commented on the internal investigation saying: "From my view issues of national security have unfortunately been reduced to a bad episode of 'Real Housewives.' The photos should not undermine the fact that the agent responded in a timely way and appropriately, nor do they reflect any amorous relationship."