The remains of a South Korean soldier killed in a northwestern North Korean town during the 1950-53 Korean War were reunited with family 66 years after his death and a posthumous journey to the United States, the defense ministry said Thursday.

Pfc. Lim Byung-geun was one of 12 South Korean soldiers whose remains were accidentally excavated by a U.S. team that was repatriating its own Korean War dead in 2001.

Under a mutual agreement with the North, the U.S. was excavating the site of the Changjin Lake Campaign, which is remembered as one of the most hard-fought battles of the three-year civil war.

The remains were brought to the headquarters of the U.S. Joint POW/MIA Accounting Command (now named Defense POW/MIA Accounting Agency) in Hawaii before the U.S. set apart the remains of the 12 South Korean soldiers as non-American forces.

"If North Korea knew the remains were those of South Korean soldiers, bringing them out of the country would have been impossible because the agreement allowed shipment of only American soldiers," the Ministry of National Defense said in a statement.

In May 2012, the remains of the dozen South Korean soldiers were brought back to South Korea, and the identifications of only two of them had been confirmed until the ministry successfully tracked down Lim's relatives.

According to Lim's family, he joined the U.S.' 7th Marine Regiment as a member of the Korean Augmentation Troops to the U.S. Army, or KATUSA, in August 1950. He was 20 at the time.

The military said Lim traveled a total of 21,000 kilometers -- from his hometown of Busan, to the North Korean battle site where he died and then to Hawaii and back to Seoul.

Lim's remains, meanwhile, were delivered to his 71-year-old nephew Lim Hyun-sik who now lives in Busan, South Korea's second-largest city, earlier in the day, the ministry said.

It said while Lim has been returned to his family, the remains of the rest of the nine soldiers killed remain unidentified, according to the ministry.

On April 28, the U.S. will send home another batch of 15 South Korean soldiers' in a ceremony to be held at the ROK-U.S. Combined Forces Command.

In the ceremony, South Korea will deliver the remains of two U.S. soldiers found in South Korea's front-line regions to the U.S. side.

"The remains of some 40,000 South Korean war heroes are believed to be buried north of the Demilitarized Zone, we are ready to bring them home if only North Korea would agree to it," Col. Lee Hak-kee, in charge of the ministry's remains excavation mission, said in the statement. (Yonhap)