World Bulletin / News Desk
Marking the 65th anniversary of the 1950-53 conflict's armistice, the Air Force transport aircraft flew from South Korea early in the morning before returning from the North to Osan Air Base south of Seoul around 11 a.m. (02:00 GMT).
Sources cited by local news agency Yonhap said there were about 55 sets of remains on board.
They will be inspected before a planned ceremony next Wednesday.
North Korean leader Kim Jong-un agreed with U.S. President Donald Trump on June 12 to the "immediate repatriation" of remains that had already been identified.
The White House welcomed the move, highlighting that the North Korean leader "is fulfilling part of the commitment he made to the President to return our fallen American service members".
"We are encouraged by North Korea’s actions and the momentum for positive change," said the office of the White House Press Secretary in a statement.
"Today’s actions represent a significant first step to recommence the repatriation of remains from North Korea and to resume field operations in North Korea to search for the estimated 5,300 Americans who have not yet returned home," the statement said.
As the American side was kept waiting, the matter was discussed when the U.S.-led UN Command held general-level talks with North Korea for the first time in nearly a decade earlier this month.
Before this latest development, official U.S. statistics showed that 7,699 American Korean War participants were still unaccounted for.
Meanwhile, the two Koreas will hold their own general-level military meeting next Tuesday, according to Seoul's defense ministry Friday.
Pyongyang apparently suggested the talks, which follow April's inter-Korean summit and their joint accord to ease border tensions.