Nearly a decade since bodies were found across Long Island's South Shore, the killings remain unsolved. What has caused the delays?

The disappearance and death of Jersey City escort Shannan Gilbert remains one of the greatest mysteries in the unsolved Long Island serial killer case. Gilbert was last seen alive in May 2010 in Oak Beach. Her last moments were recorded on a 911 call that she made as she ran from a home.

It took over a year to find Gilbert's body and the autopsy ruled her death "inconclusive." Richard Dormer, police commissioner at the time, said it was likely accidental.

Gilbert's family said it can't be coincidence that her body was found near the body or body parts of 10 other people.

But now, current Suffolk Police Commissioner Geraldine Hart says, "We're open to the idea that it could have been a murder, we're open to the idea it could have been accidental."

Over the last 10 years, there have been other disagreements and delays that experts say likely hampered the investigation. That includes the actions of then-Police Chief James Burke. News 12 has reported for years that Burke had blocked the FBI from assisting in the Gilgo Beach investigation. Commissioner Hart, who was in the FBI back in 2010, says the Suffolk DA at the time also kept the feds out.

"There was definitely an intentional decision made by both the district attorney at the time, Tom Spota, and the administration, that included Jim Burke, to keep the FBI out of the heart of the investigation," says Hart.

Spota and Burke have both since been convicted in federal court of other crimes. The FBI is now fully involved, but the Gilberts' civil attorney John Ray continues to accuse the Suffolk County Police Department of not being fully transparent. He wants the department to make Gilbert's 911 call public.

Hart says there has been no intentional decision to not release the tape, she says they are prohibited by law.

Ray still has a pending civil lawsuit against Oak Beach resident Dr. Peter Hackett, who inserted himself into the spotlight by calling Gilbert's mother two days after she went missing and then denying that call to News 12.

News 12 spoke to Dr. Hackett's attorney James O'Rourke, who says the accusations against his client have "devastated his life since it happened."

"He said basically 'your daughter was here, I hope she's fine, if I can do anything to help,'" says O'Rourke. "This is a classic example of no good deed goes unpunished by him getting involved with something that he had nothing to do with whatsoever."

So what's next in this mysterious investigation? News 12's Eileen Lehpamer takes a look at that in part 3, airing Thursday starting at 5 p.m.