Washington ? An FBI laboratory analysis of clothing found with former federal intern Chandra Levy’s remains provided no clues about her killer’s identity, law enforcement officials said Thursday.

Police hoped that Levy’s T-shirt, running bra, leggings and exercise shoes would hold microscopic traces of blood, hair, fibers or semen that could lead them to her attacker.

“There was nothing useful,” said a police official, speaking on condition of anonymity.

Sgt. Joe Gentile, a Washington police spokesman, would not comment on the results of the lab work. “The case is still under investigation,” Gentile said.

A man walking his dog and looking for turtles found Levy’s remains May 22 on a steep hillside in Rock Creek Park, nearly 13 months after she disappeared. She was 24.

Her case drew national attention because of her relationship with Rep. Gary Condit, D-Calif. Condit, 54 and married, reportedly told police he and Levy, a constituent from Modesto, Calif., were having an affair, but police do not consider him a suspect in her death.

Although Levy’s remains did not show conclusively how she died, police believe she was killed where her remains were found or nearby.

Dr. Jonathan Arden, Washington’s medical examiner, said he found no evidence of shooting, stabbing or beating. Strangulation remains a possibility, he has said.

So little could be gleaned from the bones because her body lay undetected for more than a year in a park teeming with wildlife and through changes of season. Search teams that went through the park in the weeks after Levy vanished inexplicably missed the part of the sprawling park where she eventually was found.

Law enforcement officials and forensics officials have said valuable evidence probably was lost in that time.

Investigators are focusing on the park, including its employees and people who exercise there, in their search for Levy’s killer.

They have all but ruled out two men who were convicted of violent crimes against women in the park last year.