RIVERHEAD, N.Y. (CBSNewYork) – A civil lawsuit has been filed in the case of the death of Shannan Gilbert, whose body was among ten found at Long Island’s Gilgo Beach.

WCBS 880 Long Island Bureau Chief Mike Xirinachs On The Story

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Gilbert’s mother filed the suit against the last known person believed to have seen her daughter alive.

“We also allege in this lawsuit that by his act, he caused the death of Shannan Gilbert,” family attorney John Ray said Thursday.

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No one has ever been criminally charged in the case and the suit alleges that Dr. Charles Hackett failed to meet his legal obligation as a physician to care for the 24-year-old who was later found dead in a a marsh near his Oak Beach home.

“I do believe in my heart that Dr. Hackett did play a major role in my daughter’s death,” Mary Gilbert said.

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The suit seeks unspecified damages, but Ray said it would be in the millions.