The F.B.I. is investigating a Pentagon official for allegedly giving classified information to the Israelis. This Washington Post article and this Knight Ridder article explain most of what is known about the investigation. This Washington Monthly article explores the background of the investigation by explaining that:

"The focus of the investigation, according to U.S. government officials, is Larry Franklin, a veteran Defense Intelligence Agency Iran analyst now working in the office of the Pentagon's number three civilian official, Undersecretary of Defense for Policy Douglas Feith.

The investigation of Franklin is now shining a bright light on a shadowy struggle within the Bush administration over the direction of U.S. policy toward Iran. In particular, the FBI is looking with renewed interest at an unauthorized back-channel between Iranian dissidents and advisers in Feith's office, which more-senior administration officials first tried in vain to shut down and then later attempted to cover up."