WASHINGTON (AP) — Rep. Gary Condit has taken and passed a lie detector test, a source close to the California Democrat said Friday. It was unclear what questions were asked and who administered the test.

Police and Condit's lawyers had been negotiating the limits of a test since Tuesday. Police had been pressing for no restrictions on questions related to the disappearance of former federal intern Chandra Levy, while Condit's lawyers said they wanted limitations.

The Condit source declined to provide any details about the test. Abbe Lowell, Condit's attorney, planned a news conference.

Meantime, police said they had searched more than 70 vacant buildings in the nation's capital looking for Levy, who was last seen April 30.

Capt. Willie Smith said officers under his command were trying to get through 100 buildings in the neighborhoods near Levy's apartment. "We just want to make sure all the bases are covered,"he said.

Police conceded it was a lack of good leads, rather than specific information, that led them to look at abandoned properties as places where someone could have left a body.

Police say they are pursuing four theories about Levy: She was murdered; she killed herself; she went into hiding or she has amnesia. However, police say they have all but ruled out suicide since so much time has passed and no body has been found.

Authorities planned Friday to release simulated images of Levy with different hair styles.

Police have said repeatedly they do not consider Condit a suspect in Levy's disappearance. A police source has said the congressman acknowledged a romantic relationship with the former Bureau of Prisons intern, despite denials from his office.

Levy's mother first suggested Condit take a lie detector test, saying she did not believe he had shared with police all he knows about her daughter.

A broad polygraph test offers the most accurate results, police and polygraph experts say. Lowell has said he feared that would allow questioning on matters other than Levy's disappearance.

Police wanted the FBI to administer the test. It was unclear whether that occurred or Condit hired an examiner.

Passing a test could be considered a help to Condit.

But the tests are risky for anyone facing possible criminal charges and perhaps especially so for Condit, said Irwin Schwartz, president-elect of the National Association of Criminal Defense Lawyers.

"Somebody in a congressman's position has lost the war with the first breath of scandal. A polygraph may actually do a congressman less good than it would an average person," he said.