WASHINGTON >> A Navy officer jailed in Japan over a car crash that killed two Japanese citizens has been transferred into American custody and is being returned to the United States, his family said today.

Lt. Ridge Alkonis had been serving a three-year prison sentence after pleading guilty to the negligent driving deaths of a woman and her son-in-law in May 2021. Alkonis’ family has said the crash was an accident that was caused when he lost consciousness while on a trip to Mount Fuji. Japanese prosecutors maintained that he fell asleep while drowsy and shirked a duty to pull over as he became fatigued.

“After 507 days, Lt. Ridge Alkonis is on his way home to the United States. We are encouraged by Ridge’s transfer back to the United States but cannot celebrate until Ridge has been reunited with his family,” his family said in a statement. The Alkonis family, who live in Dana Point, California, said they appreciated the U.S. government’s efforts to bring about the transfer.

The case had generated substantial publicity over the past year and a half and became a periodic point of tension between the two allies.

His family and supporters rallied had outside the White House to call for his release. Sen. Mike Lee, R-Utah, repeatedly urged Japan to transfer Alkonis to U.S. custody. Alkonis’ wife, Brittany, spoke briefly with President Joe Biden after his State of the Union address to Congress in February. And Biden raised the case during a May meeting with Japanese Prime Minister Fumio Kishida.

It was unclear how much additional time Alkonis might be required to spend behind bars in the U.S. under the terms of his transfer from Japan, which was done through a Justice Department program that permits the relocation of prisoners convicted in another country back to their home nation. The program stipulates that the sentence cannot be longer than the one imposed by the foreign government. The U.S. Parole Commission determines the release date in the cases of returning Americans.

His family says no prison time is appropriate.

“When the Biden Administration is presented with the complete set of facts and circumstances surrounding the case, we’re confident they will promptly recognize the absurdity of Ridge’s conviction,” the family said. “We trust that the (Department of Justice) will urgently wish to end this travesty of justice by immediately releasing Ridge, and we look forward to Ridge enjoying the holidays at home with his wife and children.”

A department spokesperson referred a request for comment to the Bureau of Prisons, which said Alkonis was not in its custody.

Alkonis is a specialist in underseas warfare and acoustic engineering who at the time of the crash had spent nearly seven years in Japan as a civilian volunteer and naval officer.

In the spring of 2021, after a period of land-based assignments, Alkonis, a Southern California native, was preparing for a deployment as a department head on the USS Benfold, a missile destroyer.

With the assignment looming, he set out for an excursion of Mount Fuji for hiking and sightseeing with his wife and children. They had climbed pat of the mountain and were back in the car, heading to lunch and ice cream near in a town near the base of Mount Fuji, when, his family says, he suddenly lost consciousness after suffering acute mountain sickness.

He was so out of it, they say, that neither his daughter’s screams to wake up nor the impact of the collision roused him. His car veered into parked cars and pedestrians in a parking lot, striking the woman and her son-in-law. They both died later.

After the crash near Fujinomiya, Alkonis was arrested by Japanese authorities and was held for 26 days in solitary confinement at a police detention facility, was interrogated multiple times a day and was not given medical treatment or an evaluation, according to a statement of facts provided by a family spokesman.

That statement said that when American authorities arrived to take Alkonis into custody and return him to a U.S. base, he already was held by the Japanese.

He was indicted on a charge of a negligent driving, resulting in death, and was sentenced that October to three years in prison. Relatives have said they were encouraged by Alkonis’ lawyer to have Alkonis cooperate, plead guilty and pay restitution to the victims’ family, signing a roughly $1.65 million settlement.

Though the judge in the case expressed skepticism over the mountain-sickness claim, Alkonis’ family has consistently maintained that the crash was nothing more than a terrible accident.

“The word that comes to our mind is fairness. We want him to be treated fairly for an accident,” Alkonis’ father, Derek Alkonis, said in an interview last year with the AP. “We don’t feel like it’s been that way. We know it hasn’t been that way. And it concerns us that our son has been given a three-year prison sentence for an accident.”