Nearly 400 South Koreans crossed the heavily armed border into North  Korea on Tuesday to be reunited, in an outpouring of emotions and tears, with family members separated for more than six decades since the 1950-53  Korean War. 

Participants, some as old as 88, were reunited at the resort of Mount Kumgang just  north  of the militarized border with children and spouses from whom they had been separated when the peninsula was divided at the end of the war.

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Families separated since the war have no means of communication and often do not know if relatives on the other side are surviving.

In the first round of reunions starting Tuesday, 96 North Koreans and their families met about 390 people traveling from the South. The second round will reunite about 190 North Koreans with 90 South Koreans and their families.

The South Koreans, mostly elderly and some in wheelchairs, had gathered on Monday in the east coast city of Sokcho near the border for medical check-ups and a briefing on appropriate conduct while in the North .

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The reunions, held in a ballroom at the Mount Kumgang resort, are watched by officials and media and include only two hours of private time before they end on Thursday.

South  Korean participants are advised to steer clear of a long list of topics, such as the North 's political leadership or living standards, to the frustration of some of the visitors. 

Before leaving on Tuesday for a reunion with his elder brother in the North, Kim Ki-joo struggled to frame the questions he would ask at their first meeting in 65 years.

"It is thrilling, but I can't organize my thoughts," Kim said. "I can't think of what to say. We are being reunited after 65 years, when I was 11. I want to ask if he can recognize me."