By Agence France-Presse The remains of some of the presumed US troops that North Korea returned to America appear to be from the site of a famous Korean War battle, officials said Thursday. US troops carry the presumed remains of American Korean War soldiers during a repatriation ceremony in Pearl Harbor (AFP / MANILA BULLETIN) When Pyongyang handed over 55 sets of remains last month, North Korean officials included written information about where the bones had been found, providing researchers with vital clues. John Byrd, chief scientist at the Defense POW/MIA Accounting Agency (DPAA), said a lot of the boxes came from a village called Sinhung-ri, in the vicinity of where the Battle of Chosin Reservoir took place in November and December 1950. The brutal battle between US and Chinese troops in northeast North Korea saw thousands of US Marine and Army casualties, with an estimated 1,000 Americans deemed missing afterward. "These are remains associated with the famous battle," Byrd told Pentagon reporters. The area around the site has yielded results previously, with remains being uncovered there during the 1990s and early 2000s. On Wednesday, 55 sets of remains were repatriated to the US, where they were received at a ceremony in Hawaii. Byrd cautioned that all analysis is still preliminary, but said evidence seen so far "is consistent" with the remains being American. Many nations fought in the Korean War, but war artifacts that came with the remains -- such as buttons, belts, canteens and boots -- point to the bones being American, he said. A US identity tag was also uncovered. It will be presented to relatives in Arlington, Virginia next week. 'Guardedly optimistic' Byrd said some of the remains appear to have come from the eastern side of the battle site, which was where mainly Army personnel fought. The scientist said the remains were consistent with being from the Korean War. He noted that the North Koreans had taken great care with the body parts, though the bones themselves were in varying condition. "They had been very carefully packaged with padding and packaging that was done to I think a very high standard," Byrd said in a video call from Hawaii, where the DPAA has a large lab. "That surprised me a little bit, that they took put that kind of care into the effort." Wednesday's repatriation marked an important step after US President Donald Trump and North Korean leader Kim Jong Un held a summit in June, during which Kim agreed to send home the war dead. The men also discussed launching new recovery efforts involving US-led teams going into North Korea, a process that was stopped more than a decade ago amid worsening tensions. "We are guardedly optimistic that this repatriation is the first step of others to account for the missing from the Korean War," DPAA director Kelly McKeague said. Scientists have a variety of tools to identify the dead, the most important being DNA samples that can be compared against a data base of relatives. But other techniques such as comparing teeth to dental records and bones to chest X-rays are also used. More than 5,300 US troops are still missing in North Korea.