A half-dozen visits to Levy's apartment building still leave police with "far too many people, more than a handful," who have yet to be interviewed about her disappearance, Executive Assistant Police Chief Terrance Gainer said.
Police do not expect to find someone responsible for her disappearance, Gainer said. But the people who live closest to a missing person frequently can supply important information about her actions and possible visitors in the days before the disappearance, he said.
"It's part of the irritating thing about this. We've been to the building a half-dozen times, we've knocked on doors three or four times and now we've slipped notices under the door," Gainer said in an interview. "But this is America and absent acting like jack-booted thugs, we can't force them to talk to us."
Levy, 24, of Modesto, Calif., has not been seen since April 30, when she canceled her membership at a Washington gym.
"If the police or FBI have anything new they want to discuss, we're happy to cooperate," said the spokeswoman, Marina Ein.
In a July 6 interview with police, Condit, 53 and married, admitted to an affair with Levy, a police source has said.
Police have said they do not consider Condit a suspect in Levy's disappearance, which they are treating as a missing person case, not a crime.
Ein declined comment o a possible time or place for a fourth meeting, which police officials have said could happen this week.
A CBS News poll finds most of the people Condit represents believe he has impeded the police investigation and has asked at least one other woman to lie about a sexual relationship.
Investigators want to enlist Condit's help in developing a profile of Levy, a former intern at the U.S. Bureau of Prisons, as a possible crime victim, Gainer said.
An FBI behavioral psychologist probably would sit in on the interview and attempt to elicit from Condit some information about where Levy may have gone or who may have targeted her, assuming she was harmed, Gainer said.
Gainer said Condit may also be asked about a watch box he apparently discarded in a trash can in an Alexandria, Va., park, hours before police began searching his apartment late in the evening of July 10.
"We want to follow up to find out what there is to it," Gainer said.
But police do not believe the watch box has any relation to Levy's disappearance, officials said.
When police searched Levy's apartment, they found her packed bags and most of her possessions. Levy's keys were missing. Her parents expected her back in California by May 11.
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