North Korea has rejected South Korea's request to confirm whether three South Korean high school students who Seoul believe were abducted by the North decades ago are still alive.

A Unification Ministry official on Monday said that Pyongyang recently stated that it's impossible to confirm whether they are dead or still alive. The official did not say whether North Korea had confirmed allegations of their kidnapping.

Choi Seung-min, Lee Min-gyo and Hong Keon-pyo, who went missing between 1977 and '78 on Hongdo Island, South Jeolla Province, are three out of five high school students believed to have been spirited away by communist agents in the late '70s.

The family in South Korea of Lee Myung-woo, also one of the five, has applied for a reunion with their North Korean kin. The official said Seoul will ask Pyongyang to confirm Lee's whereabouts as the first priority for future inter-Korean reunions.

The South Korean government has handled the five student abductions as separated family cases.

The issue drew keen media attention last week as North Korea allowed one of them, Kim Young-nam, to meet his family members in South Korea. During a reunion in North Korea, Kim said he went to the North accidentally while drifting at sea aboard a small boat, and denied being kidnapped.