There is no indication of criminal activity on the part of Petraeus or that he disclosed classified information, senior federal law enforcement officials told Fuentes.

Kelleys' financial troubles

Kelley hosted top military brass at her home, but it's unclear if Allen or Petraeus were aware that her family was experiencing financial difficulties or of the unusual background of a charity they founded.

Public records show that in April 2010, about six years after the Kelleys bought their $1.5 million home, Regions Bank filed to foreclose on the property, saying the couple hadn't made a mortgage payment since September 2009.

Florida records show there are at least nine lawsuits involving money and the Kelley family, including unpaid credit card bills of more than $320,000.

Public records also show the Kelleys founded a cancer research charity in 2005 called the Doctor Kelley Cancer Foundation. In a 2008 federal tax return, the Kelleys' charity reported it spent the exact amount of money it raised:$157,000.

The charity's money paid for parties, transportation, legal bills and other administrative costs. There is no evidence any of the money was used for cancer research or caring for cancer patients.

Asked for the Kelleys' side of the story, a source close to the family told CNN the source didn't have enough information to respond.

Broadwell's security clearance

It appears unlikely that Broadwell would face prosecution in the case, a senior law enforcement official said.

Officials continued to review materials taken from her home, and the FBI needed a presumption that there were classified materials there when they obtained a search warrant. But it appears that any violations of releasing classified information appear not to be egregious.

Before the warrant was issued, FBI agents approached high-level Pentagon officials to ask them if material they had tied to Broadwell could be considered classified, two U.S. officials with direct knowledge of the case said. Defense Department officials said they were classified.

As a military reservist, Broadwell had security clearance but presumably would have no clear reason to have classified information in her home, the officials said. The military has many safeguards in place, including not allowing data to be saved on hard drives and restricting what can be sent out by e-mail, to prevent secret info from getting out.

Broadwell's security clearance with the government has since been suspended, pending the outcome of the investigation, said the officials.

Petraeus reportedly has not been following the media firestorm over the extramarital affair that led to his resignation.

"He wants to maintain a distance and focus on his family at this time," his aide, retired Col. Peter Mansoor, has said.

The affair with Broadwell ended about four months ago, Mansoor said, though the two remained in contact afterward, as she needed his help to finish her dissertation.