Investigators are probing whether contamination at a city laboratory could have led to the match between DNA found at the murder scene of a Juilliard student eight years ago and a chain used at a recent Occupy Wall Street protest, law enforcement sources said Wednesday.
Two sources said investigators are looking at an NYPD lab technician and whether that technician came in contact with both pieces of evidence, causing the match, NBCNewYork.com reported.
Earlier in the day, a spokeswoman for the medical examiner's office said all employees there were screened as possible source of the DNA and that all of the medical examiner's employees were ruled out as the source of possible contamination.
Further testing to try to finalize the source of the DNA is continuing, the medical examiner's spokeswoman said.
"We are still actively investigating the DNA match," said the spokeswoman, Ellen Borakove.
NBC 4 New York reported Tuesday that DNA evidence from the scene of Sarah Fox's murder in Inwood Hill Park in 2004 has been connected to DNA from a chain left at the Carroll Street F station in Brooklyn during a protest at 7:05 a.m. on March 28.
Police Commissioner Ray Kelly said Wednesday that he could not comment on the case.
Fox was found nude and strangled in the park in May 2004, days after she disappeared during a daytime jog. Investigators recovered her pink CD player in the woods just yards from her body.
Dimitry Sheinman, 47, has long been considered a suspect in the Fox murder. He was never charged in the case and has been living in South Africa.
Sheinman recently returned to New York City, proclaiming to be a clairvoyant with knowledge of the killer's identity. He asked to meet with police to give them information about the alleged killer; the details he offered are unknown.
Sources said Sheinman remains a leading person of interest. His DNA, which police have on file, was not found on the chain or at the 2004 murder scene. The DNA of the crime-scene detective who handled the chain has also been ruled out, sources said.
Sheinman did not respond to a request for comment.
In March, protesters chained open emergency gates and taped up turnstiles in eight subway stations and posted fliers encouraging passengers to enter for free.
"I hope the person or persons who killed this young woman are found and brought to justice," said Bill Dobbs, a spokesman for Occupy Wall Street. "We don't know anything about it ... I hope no one jumps to any conclusions."
No one was arrested in the March subway protest incidents.
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