Updated

The remains of two Civil War soldiers have been discovered in a surgeon’s burial pit at Manassas National Battlefield Park in Virginia.

“This is the first time in history that a surgeon’s pit at a Civil War battlefield has been professionally excavated and studied,” explained the National Park Service, in a statement. “It is also the first time that killed-in-action Civil War soldiers have been found in an amputated limb burial pit.”

The discovery was first made by the National Park Service in 2014. Officials then worked with forensic anthropologists at the Smithsonian’s National Museum of Natural History to excavate the site and recover the remains.

ABRAHAM LINCOLN LETTER MYSTERY 'ALMOST CERTAINLY' SOLVED, EXPERTS SAY

In addition to the soldiers’ remains, 11 amputated limbs were also found in the hastily dug pit, confirming that it was the site of a field hospital. The complete remains belong to two Caucasian males aged between 25 and 34 years of age that died at the second battle of Manassas.

ManassasSkeleton

Excavation of an amputated limb (Credit: Kate D. Sherwood, Smithsonian Institution) (This image was obtained from the Smithsonian Institution. The image or its contents may be protected by international copyright laws.)

The first battle of Manassas took place on July 21, 1861. The second battle of Manassas occurred between August 28 and 30, 1862. Both battles, (which were known as the first and second battles of Bull Run by Union forces), resulted in Confederate victories.

“One of the soldiers was found with an Enfield bullet still lodged in his upper thigh bone (femur),” explained the National Park Service, in its statement. “The other soldier was found with three fired lead buckshot. It is likely that a field surgeon determined that both soldiers had injuries too severe to be operated on successfully.”

NORTH CAROLINA BEACHGOER CAPTURES DRONE FOOTAGE OF CIVIL WAR-ERA SHIPWRECK

Experts believe that the soldiers are likely from the Union army, noting that Enfield bullets were used almost exclusively by the Confederate Army at the Second Battle of Manassas. Buttons from a Union jacket were also found with the remains of the man who died from buckshot. Isotope analyses by forensic anthropologists also showed the men consumed food and water from Northeastern region while their bones were forming.

The soldier will be interred at Arlington National Cemetery later this year in coffins built from a downed tree from the battlefield. The burials will be the first in the cemetery’s Millennium Expansion, which plans to add nearly 30,000 burial sites and niche spaces to the site.

“Later this summer, we will have the great honor to inter these unknown Soldiers with their fellow Soldiers at Arlington,” in a statement. “They will lay to rest in our new Millennium Expansion as we commemorate their ultimate sacrifice 156 years ago at the Second Battle of Manassas.”

NORTH CAROLINA BEACHGOER CAPTURES DRONE FOOTAGE OF CIVIL WAR-ERA SHIPWRECK

America’s Civil War sites and artifacts from the era regularly offer fresh glimpses into the bloody conflict. Earlier this year, a holidaymaker on a North Carolina beach captured drone footage of Civil War-era shipwreck.

Last year, forensic linguists said they have likely unraveled the mystery surrounding a famous Civil War-era letter, long believed to have been written by President Abraham Lincoln.

In 2015, the remains of a Confederate warship were raised from the Savannah River in Georgia. The following year, the wreck of a large iron-hulled Civil War-era steamer was discovered off the coast of North Carolina. The ship, which was found off Oak Island, N.C, was tentatively identified as the blockade runner Agnes E. Fry.

Fox News’ Madeline Farber and the Associated Press contributed to this article.

Follow James Rogers on Twitter @jamesjrogers