The bodies arrive by the hundreds on a dusty railroad platform, nameless, mutilated, unearthed from mud, sand or collapsed trenches. In quick procession, they are unloaded in their white bags from a refrigerated car and wheeled to a trackside field lab, where they are examined and documented with quiet efficiency.
This vast shipment of the dead, returned by Russia in a swap with Ukraine, is one of the few results of three rounds of American-orchestrated cease-fire talks. Those negotiations and a summit on Friday between President Trump and the Russian leader, Vladimir V. Putin, have done little to slow the fighting on the battlefield.
Ukraine hopes to identify each of the 6,000 bodies it has received from Russia under a deal reached in Istanbul — which also included a prisoner exchange — and return the soldiers’ remains to loved ones.
The bodies are just a fraction of the more than 70,000 people in Ukraine, both military personnel and civilians, who have been listed as “missing under special circumstances,” the legal designation for those who have disappeared during more than three years of war.
The first remains arrived in Ukraine in June. A conveyor-belt-like process at a railway station in the Odesa region in southern Ukraine is intended to speed up identification, bypassing traditional autopsies in morgues, which are already overloaded.
Six teams in total carry out forensic work under a section of the platform shaded by camouflage netting stretched to block the searing summer sun. Each team includes a police investigator, a forensic technician, a pathologist, an intelligence officer and a sanitation worker.
“We are the first in Ukraine to organize this kind of work,” said Tetyana Papizh, the head of the regional forensic bureau.
The bodies are moved from station to station in a process that takes about 20 to 30 minutes for each. Workers check for explosive materials, document any personal items found with the remains and take samples for DNA testing.
When possible, the teams perform fingerprinting using a technique in which fingers are soaked in water heated close to boiling, then injected with cold water to restore fingerprints.
The bodies receive 17-digit identification numbers, encoding the date of arrival, the institution that received the body and an individual sequence number.
Documents, tags, jewelry or scraps of clothing retrieved from the bodies can help in identification. If any are found, a technician photographs them, bags them separately and places them back with the remains in a new body bag.
“Personal items are extremely important,” said Andriy Shelep, a senior police investigator working on crimes committed during the war. “Some families don’t trust DNA results. They won’t accept death. They believe their loved one is still in captivity. But when they see the recovered items, the doubt is gone.”
Tension from working with the dead is unspoken but present in every movement on the railway platform, where the air was thick with the smell of decay.
Ruslana Klymenko, 27, a pathologist, leaned over a half-decomposed body. Stains from body fluids had penetrated multiple layers of her protective suit. On her head, she had tied two pink ribbons, the only bright element in a dim scene under the camouflage nets.
“Lower jaw is missing,” she said to an investigator, who documented the finding.
Every few minutes, another white bag was laid out on the table and opened. What looked like rags and dirt inside may be putrefied tissue.
In an exchange last month with Russia, which is to receive an equal number of bodies, 1,600 remains were sent to the location in the Odesa region. An additional 1,000 bodies arrived in Ukraine on Tuesday. The Russian news media has not reported widely on the return of Russian bodies, mentioning only several shipments of a few dozen sets of remains.
Identification of all 6,000 remains may take more than a year, according to the country’s internal affairs minister, Ihor Klymenko. The process is complicated, he said, by the fact that some body bags contain parts of more than one person.
Among those who had awaited the return of a loved one was Tetyana Dmytrenko of Kyiv, the capital. Her husband, Oleksandr Dmytrenko, was killed at age 45 along with all others in his unit on Nov. 15, 2023, near Bakhmut, she said. Russian forces took control of the area, and recovery of the bodies was not possible.
“All I had left was his last text message — ‘I love you,’” Ms. Dmytrenko said. “Then came a year and eight months of waiting, of not knowing, that was worse than hell.”
On June 23, Ms. Dmytrenko received a call from a police investigator who told her that DNA from one of the returned bodies matched that of Maryna, their 21-year-old daughter. Ms. Dmytrenko visited a morgue for the formal identification, though she said there was nothing left to recognize.
She remembers her husband telling her that his greatest fear was dying in battle and never being recovered. “Now I have peace in knowing that he is home,” she said.
Andrew E. Kramer contributed reporting from Kyiv, Ukraine.