(Updates with reunion event, quotes)
By Michelle Kim and Narae Kim
SEOUL, Feb 20 (Reuters) - More than 100 South Koreans, many of them on wheelchairs, crossed the world's most heavily fortified border on Thursday to be reunited with family members living in the North whom they have not seen since the 1950-53 Korean War.
The reunions were held after the North set aside a demand for the suspension of joint military drills by the South and the United States, which it had demanded as a pre-condition.
At the Mount Kumgang resort just north of the border, long-lost relatives embraced with tears, joy and disbelief. Some failed to recognise family they have not seen in more than six decades.
Among the South Koreans was Jang Choon, an 81-year-old in a wheelchair who was dressed in the light brown suit and maroon tie he had bought for the reunion with a brother and a sister living in the North.
"My youngest brother Ha-choon had not even started school when I last saw him," said Jang, the eldest of four siblings, one of whom has died. "But now he's an old man like me."
The six days of family reunions take place under the cloud of a U.N. report on human rights abuses in North Korea, which investigators have said were comparable to Nazi-era atrocities. They have said North Korean security chiefs and possibly even leader Kim Jong Un himself should face international justice.
Pyongyang has rejected the report, describing it as a concoction by the United States and its allies, Japan and the European Union.
But the North appears to be willing to maintain a rapprochement with South Korea that may be crucial as it seeks food for its people.
The possibility of looming food shortages could have been a factor.
"Now it's almost March, when the new farming season must begin, and Kim Jong Un has no means to feed his people," said Kim Seok-hyang, professor of North Korean studies at Ewha Womans University.
"He must get outside help. But looking around, the U.S. won't give him anything, China doesn't seem willing to give anything and then there's the U.N. human rights report pressuring him. The family reunions card is his last resort because he can't neglect his people."
CAN'T DIE WITH MY EYES CLOSED
The reunions used to be held roughly annually, but have not taken place since 2010 as tensions between the two Koreas spiralled after the South said the North sank one of its naval vessels. In later months, the North shelled a South Korean island and Pyongyang threatened nuclear attacks last year.
For many of those making the trip to Mt. Kumgang, it will be the last chance to meet separated loved ones.
Of the 128,000 people registered in South Korea as coming from families that were torn apart by the Korean War, 44 percent have already died and more than 80 percent of survivors are over 70, according to South Korea's Unification Ministry, which handles inter-Korean relations.
There have been 18 family reunions since the first in 1985 and a total of 18,143 South and North Korean brothers, sisters, fathers and mothers have met.
The events have never been regular and the two Koreas have squabbled over the details of the events, like deciding on the venue. After the first four, in which families traveled back and forth between Seoul and Pyongyang, North Korea has insisted on hosting the events on its soil.
"The North fears exposing their people to the outside world so they want to shroud their people from looking at the South's successful way of life," said Kim, the professor.
For the families, the politics are secondary.
"I swore to myself, I must not die before I meet my brother and sister," said Jang, the 81-year-old. "I just cannot die with my eyes closed if I don't see them this time." (Additional reporting by James Pearson; Editing by Jack Kim and Raju Gopalakrishnan)
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