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.

Read the original story at NBCNewYork.com

"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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Officials have linked forensic evidence from the 2004 murder scene of a Juilliard student to the scene of a recent Occupy Wall Street subway vandalism, NBC 4 New York has learned.

Investigators have connected DNA evidence from the scene of Sarah Fox's murder in Inwood Hill Park eight years ago to DNA collected at the scene of an Occupy Wall Street subway station vandalism in March.

Fox, 21, 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.

Sources said Tuesday the DNA found on the CD player is linked to DNA found on a chain left by Occupy Wall Street protesters at the Beverly Road subway station in East Flatbush on March 28, 2012. 

Read the original story at NBC New York

That Wednesday morning, protesters chained open emergency gates and taped up turnstiles in eight subway stations and posted fliers encouraging riders to enter for free.

A "communique" posted online later that day by the "Rank and File Initiative" described the act as a protest against service cuts, fare hikes and transit employees' working conditions.

It was attributed to "teams of activists, many from Occupy Wall Street ... with rank and file workers from the Transport Workers Union Local 100 and the Amalgamated Transit Union."

Sources said they have not connected a person to the common DNA found on the CD player and the chain. There's no immediate evidence that the DNA belongs to the Occupy Wall Street protesters who chained open the gates.

No one was arrested in the March incidents. Police are continuing to investigate, and are now working to identify the source of the DNA found in common with the chain and the CD player.

Dr. Lawrence Koblinsky, a forensics expert at John Jay College of Criminal Justice, said the DNA link was a major clue in the investigation, one that could potentially break the case. 

“You’ve got the same DNA left at two distinct sites," said Koblinsky. "Until they find the individual who left that DNA, we won’t know. But the likelihood is high the person who left that DNA on the CD player is the killer of Sarah Fox.”  

Dimitry Sheinman, 47, has long been considered a suspect in the Fox murder. He has since moved to South Africa and started a family. He was never charged in the case.

Sheinman recently returned to New York City, proclaiming to be a clairvoyant with knowledge of the killer's identity. The information he gave police was unclear.

Sources said he remains a leading person of interest.

Sheinman did not respond to a request for comment.

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