Initial forensic analysis suggested that the remains were likely to be those of American service members, the USA military said.
The remains will be taken to a laboratory at the base for identification and experts say the process could take anything from days to decades. Some of them, including Australia, Belgium, France and the Philippines, are yet to recover some of their war dead from North Korea.
The Rodong Sinmun, North Korea's official party newspaper, yesterday accused Seoul of "wasting time" waiting for sanctions to be lifted only after denuclearization is completed, without "taking a single action" on its own.
"But today is just the beginning", he continued. Liquid fueling can also take a fairly long time to complete, giving U.S. spy satellites a period of time to see launch preparations underway.
According to the United States official who spoke to Reuters, one photo showed a truck and covered trailer similar to those the North has used to move its ICBMs. About 5,300 were believed to be on North Korean soil. But he cautioned it was unclear if that soldier's remains were among those received from North Korea.
Byrd said a lot of military hardware - such as helmets, canteens and boots - was included in the shipment.
More than 35,000 Americans were killed on the Korean peninsula during the 1950-1953 war, with 7,700 of these U.S. troops still listed as missing in action - a lot of them in North Korea.
These are not the first reports that North Korea may be continuing its weapons programme, casting doubt on the real impact of the summit in Singapore.
Army on streets as Zimbabwe awaits election results
The MDC also questioned the pace of releasing results from the presidential vote. MDC Alliance supporters demonstrate outside the Zanu-PF headquarters.
Rick Downes, executive director of a group of families whose loved ones never came home from the Korean War, said it now appears that Pyongyang is trying to help. "We don't know who's in those boxes", Mattis said. "This should hasten identifications quite a bit".
More than 400 caskets of remains found in North Korea were returned to the United States between the 1990s and 2005, with the bodies of some 330 other Americans also accounted for, according to the DPAA.
An unidentified US defense official, however, said there was only one set of military identification tags, known as dog tags, with the remains.
North Korea suspended its missile and nuclear tests and shut down its nuclear test site, and recent satellite photos indicate it also began dismantling key facilities at its main rocket launch site.
Reports had indicated that North Korea was upgrading its only official nuclear enrichment site, and was stepping up enrichment at other secret sites.
The two sides are expected to discuss a possible cut in firearms and personnel stationed at the DMZ, as well as a joint excavation of the remains of soldiers killed in the 1950 to 1953 Korean War.
Another ceremony was conducted Wednesday as the remains were sent to Hawaii, with bugles playing taps, as well as "The Last Post", a call used at funerals by British and Commonwealth militaries, and a South Korean bugle call.
More than 7,700 US troops remain unaccounted for from the Korea War.
Major-General Kim Do Gyun, the South's chief negotiator in charge of North Korea policy at the Defence Ministry, told reporters he would make efforts to craft "substantive" measures to ease tensions and build trust. The Hwasong-15 is North Korea's longest-range ballistic missile, capable of carrying a large payload to likely all of the contiguous United States.
But the actual details of the process, including how and when the North's nuclear program is to be dismantled, have yet to be worked out.
Rep. Gabbard pays respect to the remains of service men killed in the Korean War. "Today our boys are coming home", an emotional Pence said.