Members of the Missing in America Project hold a burial ceremony for six people, including one of the iconic Buffalo Soldiers from the 1800s, on Tuesday at Arlington National Cemetery. (Bill O'Leary/The Washington Post)

They returned home after serving honorably on battlefields in Italy, France and Vietnam many years ago.

And when they died stateside, some, it seemed, couldn’t rest in peace.

One veteran’s remains went unclaimed for more than three decades; the remains of another went missing for months after his death. A third veteran was estranged from family when she died, and no one arranged for her burial.

On Tuesday, six veterans who were largely anonymous in life and death were interred with full honors at Arlington National Cemetery.

“He’s happy, and I think he would give me a big hug,” said Andrew Pincsak of his cousin Richard Pincsak, a professor and Silver Star recipient in the U.S. Army who was shot down twice over Cambodia during the Vietnam War and died in 2014. “I think he knew he was dying and just before he died, he reached out to me and talked about this — he asked if I’ve ever been [to Arlington National Cemetery] before.”

An Honor Guard folds a U.S. flag over urns bearing the remains of six veterans. (Bill O'Leary/The Washington Post)

“He told me to take care of it,” said Andrew Pincsak, who said he planned to arrange a military burial. But he initially couldn’t find his cousin’s remains at local funeral homes, and turned to one national nonprofit organization for help.

The burials were the culmination of a nearly year-long search by the Missing in America Project, a national group dedicated to finding, identifying and interring the remains of unclaimed service members.

Since 2006, the group has been to 1,857 funeral homes and found the unclaimed remains of more than 11,986 people. From that number, it identified 2,759 service members and has interred 2,496 of them in cemeteries around the nation.

Sometimes, organizers said, people call after finding urns in all sorts of places, such as the bed of a pickup truck or a storage unit. And in all sorts of containers: a plastic bag or a cardboard box, sometimes brown paper bags.

As the group headed to Arlington on Tuesday, it was as if their scores of motorcycles played their own tribute to the fallen: The guttural noise of exhaust hummed like a chorus.

During the ceremony, family members were presented with flags. And for those veterans who didn’t have a relative present, volunteers stood in for loved ones.

“There’s always this great satisfaction when they’re put to rest,” said Fred Salanti, co-founder of the project and a Vietnam veteran.

Charles Jackson, third from right, seated, returns a salute to Sgt. 1st Class James E. Simmons, left, after receiving a presentation flag. (Bill O'Leary/The Washington Post)

For Salanti, who lives in California and spearheaded a cross-country motorcycle ride to Virginia for Tuesday’s burials, the trip was soul-cleansing.

“In some sense there’s a payback,” Salanti said. “It’s an honor thing — you’re taking people that will never have something done for them.”

Andrew Pincsak said he worried that his cousin would end up in a dumpster. The 49-year-old lives in Chicago, and after Richard Pincsak died, no one in the family could find him in the Eureka, Calif., funeral homes. After some research and phone calls to a mayor and a senator, Andrew Pincsak said he found out that a friend of Richard Pincsak’s posed as a second cousin, cremated the remains and kept them. To get them back, he contacted the Missing in America Project.

Andrew Pincsak, who said his cousin was all about never quitting and “forging forward to do what’s right and help other people,” added that the ceremony felt like closure — “closure that people he didn’t know are happy he served, [for] a government that didn’t know him but know of him now and helped get him here, and family that was brought a little tighter together,” he said.

Bill Holt, a volunteer with the project since 2008, said he’s been to 150 burials for unclaimed veterans.

“They’ve given their lives for our country,” he said. “I know they’re not there physically, but spiritually they are. And to be among that is just phenomenal.”

Many of the volunteers and family members wore black at the ceremony. But volunteer Lula Lamb wore white.

Lamb, who lives in Richmond, lost a stepson, Lt. Almar Fitzgerald, in Iraq in 2006.

When asked what her stepson would think of the ceremony, and her soft sobbing, she said Fitzgerald would tell her: “Dry up those tears and smile.”

“These individuals have finally reached their burial, and now they’re at peace with their brothers and sisters,” she said. “They’re not in limbo anymore.”

Then, as if on cue, the 57-year-old straightened her shoulders to look at the urns, which were tucked away inside a shady tent that overlooked six columbarium niches, where the remains would later be placed.

“They’re tears of joy,” she said. “Today’s a good day.”

Magda Jean-Louis contributed to this report.