Gusev was the "outside man" who parked his car within line of sight of the State Department, then activated a listening device in a seventh floor conference room used by senior officials. Now the FBI is now focused on finding the "inside man," the person who planted the bug in the first place.
The device was hidden in a piece of wall molding. To put it there, someone had to first survey the room, then fabricate an identical piece of molding with the bug built into it. Then whoever it was has to go back into the room once again, with enough tools and enough time to remove the existing molding and replace it with the piece containing the device.
Intelligence officials say it has all the earmarks of an inside job by someone working in the State Department, who could make the switch without arousing suspicion. If that's the case, a Russian agent could still be at large inside the State Department.
Now hundreds of State Department and other U.S. officials are being interviewed in an attempt to find out how and when the bug was planted. But the search for a disloyal employee is complicated by the fact that the FBI doesn't know how long ago the bug was planted. It had enough battery power to have been there for years.
Secretary of State Madeleine Albright said Friday "I have no idea about" whether someone inside the State Department helped the Russian. "I was told about this several months ago and we have followed a very careful procedure," she said on CBS' The Early Show.
"We don't have a suspect," according to a government official, who described the highly secret investigation Thursday night on condition of anonymity. "We're looking at and haven't eliminated any possibility."
Other agents are interviewing all the participants in 50 to 100 meetings that occurred in the bugged conference room while Gusev was outside. Their goal is to determine exactly what he might have heard. Based solely on the topics listed on State Department logs of the meetings Gusev allegedly monitored, the government official said, "The initial reaction is that he didn't gather a lot of sensitive information, but as we catalogue what went on in those meetings, that assessment could change."
Meanwhile, Russian television continues to show reruns of last week's arrest of an American diplomat, Cheri Leberknight, for spying, suggesting the U.S. trumped up the State Department bugging charges in retaliation.
The truth is both sides still spy. U.S. officials say there are as many intelligence officers assigned to the Russian embassy today as there were during the cold war.