His remains were found in a wooden casket, a skeleton buried under the sands of a Pacific island since World War II.

His identity remains a mystery. The U.S. service member is one of 452 Americans still classified as missing in action – most killed during the Battle of Tarawa, and buried in mass graves.

Anthropologists unearthed his bones on the Tarawa atoll during the summer of 2017. The skeleton from the 1940’s has yet to return to America for DNA testing.

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But a mission by the U.S. Marines to retrieve the man’s remains was abruptly canceled late Saturday – the government shutdown suspending a recovery flight planned for Wednesday.

Even after the budget impasse ended, the Pentagon did not report immediate plans to resume the mission.

“I’m saddened that the repatriation of this American war hero was delayed because of the government shutdown,” said Dr. Hillary Parsons, the anthropologist who discovered the remains.

“No matter what your political affiliation or views, I think we can all agree that this man and his family deserve closure as soon as possible.”

Parsons is part of the non-profit group called History Flight – private anthropologists who found the largest number of missing in action remains in the history of the U.S. Armed Forces.

The Marines were set to arrive on Tarawa, islands situated halfway between Hawaii and Australia, on Tuesday.

Defense officials planned a formal homecoming ceremony for Wednesday. Marines prepared to escort the man’s flag-draped casket onto a military plane bound for Joint Base Pearl Harbor–Hickam in Hawaii.

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The Defense Department previously sent a C-130 transport plane to return the remains of 17 Americans discovered after WUSA9 visited the island in June 2017.

The casket scheduled for this week’s ceremony now rests in a lab on Tarawa, 7,000 miles from Washington.

Smaller skeletal remains were also found in the area near the casket, belonging to an unknown number of individuals. The bones and bone fragments were also set to join the latest repatriation flight.

“No new timeline yet and no sense on what is being coordinated,” said defense spokesperson Todd Livick in an email Sunday. “We will keep you posted as this develops.”

Defense officials contacted Monday did not respond for comment.

Officials said in the days before the shutdown the mission to Tarawa would not be impacted by the budget crisis. The notice of cancelation came before 6 p.m., as a WUSA9 team landed in Los Angeles, en route to Tarawa.

History Flight and Pentagon personnel anticipate the mission will be rescheduled – but the timing remains unclear.