OSAN AIR BASE, South Korea — Fifty-five cases presumed to be holding the remains of U.S. troops killed in the Korean War began their journey home Wednesday after a formal send-off at this air base south of Seoul.

North Korea handed over the remains last week, the first repatriation in more than a decade and a move that partially fulfilled an agreement reached during the June 12 summit between leader Kim Jong Un and President Donald Trump.

Hundreds of U.S. and South Korean servicemembers attended the ceremony along with dignitaries from the 15 other countries that fought in the 1950-53 war.

The cases lined up in a hangar at Osan were covered with blue United Nations flags pending final identification.

But a two-day forensic review showed that the remains appear to be human and “are likely to be American,” John Byrd, an anthropologist with the Defense POW/MIA Accounting Agency, told reporters before the ceremony.

“Our preliminary findings were that the remains are what the [North Korean] officials said they were,” Byrd said, adding that it was one of the largest unilateral turnovers ever received from the North.

“There’s no reason at this point to doubt that they do relate to Korean War losses,” he said.

Byrd, director of scientific analysis for DPAA, also confirmed a report that a single dog tag was provided with the remains and said the family of that individual has been notified.

But, he stressed, it was not known if the soldier’s remains were among those being repatriated as the North Koreans had expressed concern about co-mingling.

He said other evidence that the boxes contained American remains included military hardware such as helmets, canteens and boots.

Byrd also said scientists were confident that there were no animal bones mixed up with the remains.

Never forgotten

Gen. Vincent Brooks, who leads the U.N. Command and U.S. Forces Korea, presided over a ceremony titled “Never Forgotten,” with full honors, including a wreath laying and a rifle salute.

The cases were then loaded three by three to two Air Force planes that were to fly them to Hawaii.

One was grounded due to a maintenance safety concern, but the remains on board were transferred to a third aircraft that took off a few hours later, according to the UNC public affairs office.

Vice President Mike Pence, whose father fought in the Korean War, was scheduled to attend an “honorable carry ceremony” at Joint Base Pearl Harbor-Hickam to mark the arrival of the remains on U.S. soil.

The remains will undergo a lengthy forensics process at the military lab, which is staffed by more than 30 anthropologists, archaeologists and forensic odontologists.

Byrd said the North Koreans provided enough information about where the remains were found to place them on a battleground from 1950-51.

U.S. officials also are eager to resume searches in North Korea for more remains, an effort that has been stalled for more than a decade due to rising nuclear tensions.

“We do not know if the North Koreans have any additional remains, but I’ll tell you this is a great first step towards bringing a bunch of fallen Americans home,” Rear Adm. Jon Kreitz said during the press conference.

“We look forward to potentially pursuing operations in North Korea in the future and we’re very hopeful that again this is just a great first step in building some confidence and building a relationship,” he added.

The DPAA has what it calls family reference samples, including DNA, for more than 90 percent of the missing servicemembers.

More than 7,600 American servicemembers remain missing from the war, which ended in an armistice instead of a peace treaty.

Some 5,300 of those are believed to have been lost in North Korea, which is separated from the South by one of the world’s most fortified borders.

"Just over 1,000 men are unrecovered" from the so-called Demilitarized Zone and nearby buffer zones, according to DPAA.

Search continues

Joint U.S.-North Korean military search teams recovered 229 sets of American remains from North Korea between 1996 and 2005.

The U.S. was allowed to conduct 33 investigative and recovery operations in the country before former President George W. Bush’s administration called off the search, claiming the safety of American participants was not guaranteed.

Critics at the time also argued the North was using the program to extort money from Washington, prompting the label “bones for bucks.”

The last repatriation was in 2007, when then-New Mexico Gov. Bill Richardson traveled to Pyongyang and returned with six sets of remains.

The State Department has said no payment was made for the current sets of remains.

The Trump administration has hailed the repatriation as a significant goodwill gesture even as efforts toward persuading the North to abandon its nuclear weapons have faltered.

Kim Jong Un committed to try to work toward the “complete denuclearization of the Korean Peninsula” during the summit in Singapore, but he agreed to no specific measures or timelines.

Officials say U.S. spy agencies, citing evidence including recent satellite photos, have spotted signs that the North is building new intercontinental ballistic missiles, according to the Washington Post.

That was the latest in a series of reports casting doubt on whether the communist state is truly committed to abandoning its hard-won nuclear weapons.

The North demonstrated sharp progress in its program last year when it test-fired numerous missiles and conducted its sixth and most powerful nuclear test.

But tensions have ebbed as diplomatic efforts advanced and Kim announced his country would suspend long-range missile and nuclear tests. Experts have noted he did not promise to stop development.

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