WASHINGTON: A woman has an affair with a commander of the realm, finds another female presence near him and tries to scare her away. The other woman goes to the custodians of the realm and it ultimately brings down the commander.

“O beware, my lord, of jealousy. It is the green-eyed monster which doth mock the meat it feeds on,” says Iago to Othello.

Yes, it indeed is the plot of a Shakespearian play except that it is not a play. It is real, as real as it can be.

The affair that brought an end to David Petraeus' tenure as CIA chief came to light during an FBI investigation into a complaint that his biographer Paula Broadwell was sending harassing e-mails to another woman close to him.

But the woman, who received threatening e-mails from Broadwell, a married mother of two, apparently also spoke to a lawmaker, House majority leader Eric Cantor.

Cantor’s office said that the congressman talked to an FBI official in late October about Petraeus' involvement in an affair.

His spokesman Doug Heye told CNN Sunday that Cantor had a conversation with the whistleblower about the affair and the national security concerns involved in the matter.

But The New York Times reported that Cantor learned of the whistleblower from another Congressman, Dave Reichert, a Republican from Washington State.

When FBI sleuths discovered that the head of the world’s most powerful spy network was now paying more attention to the affairs of his heart than those of the state, they warned him.

Apparently, the warning did not have the required effect on the love-sick commander, at least not until it was too late.

These and other details of the Petraeus-Broadwell affair dominated Sunday talk shows and newspapers in the United States. Media reports said that during the investigation, FBI discovered other communications between Petraeus and Broadwell and concluded that they were having an affair.

The reports did not identify the woman who made the initial complaint and said that the officials who spoke to their correspondents did not know the nature of her relationship with Petraeus.

The FBI interviewed Mr Petraeus in the course of its inquiry but it was not clear if they also spoke to Broadwell.

In one of the talk shows, Congressman Peter King, a New York Republican, said he was confused as to why the FBI didn’t alert President Barack Obama to the affair until just last week.

“The FBI should have had an obligation to tell the president,” King said on CNN’s State of the Union. “It just doesn’t add up.”

The Obama administration first learned of the affair in a phone call from the FBI to Director of National Security James Clapper at 5 p.m. on Election Day.

Senator Bob Menendez, a Democrat from New Jersey, however, said everything about the FBI’s handling of the revelations appears proper: “I don’t see a conspiracy behind every curtain as some of my colleagues do.”

Still, the head of the Senate Intelligence Committee wants to know why the FBI didn’t tell her that agents were investigating an extramarital affair of the CIA chief.

US media reports claimed that the House and Senate intelligence committees weren't informed that there was an FBI investigation into Mr Petraeus until Friday.

Senator Diane Feinstein told ‘‘Fox News Sunday’’ that she first learned about the matter from the media late last week.

Feinstein said she called Petraeus twice on Friday and was dumbstruck when he acknowledged the affair.

The news, she said, was “like a lightning bolt” to her. Feinstein said she’s now been briefed by the FBI. She said she initially didn’t want President Obama to accept Petraeus’ resignation, but realizes now he had no choice.

The resignation also comes days before Petraeus was slated to testify before the Senate Intelligence Committee about the Sept. 11, 2012 attack on the US Consulate in Benghazi, Libya.

Some media reports even suggested that the timing of Mr Petraeus' stepping down was suspect, given the expected grilling in Congress.