It's a baffling mystery of World War II - whether dozens of U.S. sailors listed as missing from a ship explosion were actually recovered and buried as unknowns in a Long Island cemetery.

News 12's Virginia Huie brings us the story of one family's fight for answers and a proper burial for their war hero.

Behind every stone at Long Island National Cemetery is a story. The names, service and sacrifice of nearly 300,000 heroes saluted in silence with dignity and respect.

But in Section L of the hallowed ground, there's a chapter of World War II history shrouded in mystery.

Four gravestones are etched with the words "Unknown U.S. Sailor." Each one marks the final resting place of unidentified warriors lost at sea 75 years ago.

Margaret Sickles believes her brother, Fireman 1st Class Richard Duffy, is buried in one of the "Unknown U.S. Sailor" graves.

"It's sad to see it marked just 'Unknown Sailor.' He's not unknown. He was very well known with our family," says Sickles.

Duffy, then 18, was one of 136 sailors killed after the USS Turner exploded and sank near the entrance to New York Harbor on Jan. 3, 1944.

Sickles was 3 years old when her big brother shipped off to serve in World War II. She remembers the day her family in Whitehall, New York received word about his terrible fate.

"My father was in the living room listening to the news and he all of the sudden slammed the radio off," she says.

 The Pentagon classified the fallen sailors as missing in action. Duffy's family lost hope of finding closure until more than 70 years later. In 2016, military researcher Ted Darcy dug up federal documents that indicated most, if not all, of the sailors' remains were found and buried at Long Island National Cemetery.

Duffy's family is now calling on the Pentagon to exhume the graves and conduct identifications - so that the long-lost remains of the Turner can be reburied in marked grave sites with full military honors.

The American Legion is working with the family to enlist the help of New York's congressional delegation to cut through red tape.

The families face an uphill battle. While the Department of Defense reopened the case based on Darcy's findings, the investigation has since stalled. Officials say in order to justify disinterment of the graves, more paperwork must be found, including the sailors' dental records - something that could take years.

USS Turner's fallen sailors came from 31 states, including New York, Connecticut and New Jersey.