North Korea's admission that it abducted Japanese citizens, and that eight of them are dead, has been greeted with shock and anger in Japan.

I wonder if she was killed to conceal what really happened to her

Akihiro Arimoto, father of abductee

Japan is now pressing for the truth about how the victims died.

North Korea's leader, Kim Jong-il, admitted the Japanese were abducted in the 1970s and 80s to work in North Korean spy schools.

He apologised during unprecedented talks with the visiting Japanese Prime Minister, Junichiro Koizumi, on Tuesday. He said the eight Japanese died due to disease or natural disasters.

But most of the abductees were only in their twenties when they were snatched, and the grief-stricken families are demanding an explanation.

The 74-year-old father of abductee Keiko Arimoto said he had fought for the truth for a long time but was "shattered" by the news that his daughter was dead

"What I want to know now is how my daughter died. I wonder if she was killed to conceal what really happened to her," said Akihiro Arimoto.

"I'd been waiting to hear some good news but what we got was the extremely disappointing news of my daughter's death," said Shigeru Yokota, whose daughter Megumi was kidnapped in 1977 when she was only 13.

"What I really want to know is why she ended up in North Korea and how she died."

Mr Yokota and his wife Sakie are also grappling with the news that Megumi married and had a daughter, who is still alive.

Home soon

Government officials have said they will work quickly to secure the return of the four survivors.

The BBC's Charles Scanlon in Tokyo says they are expected to be repatriated by the time further talks with North Korea get under way at the end of next month.

A member of the Japanese delegation was able to meet the surviving abductees in Pyongyang.

They are two couples who disappeared in 1978 when they were in their early twenties - apparently plucked off beaches by North Korean special forces.

	Japan's missing Eight Japanese confirmed dead Four still alive in North Korea Kim Jong-il says he has punished the culprits See also: Profiles of the missing

It is thought they were abducted to teach North Korean spies to disguise themselves as Japanese nationals.

"I don't feel relieved at all," said Tamotsu Chimura, even though his son, Yasushi, was confirmed alive.

Mr Chimura said the lack of other information had only deepened his grief.

"It would almost have been better to have been told all of the missing were dead," he said.

Observers say Mr Koizumi could face a backlash from the Japanese public if he presses on with normalisation talks with North Korea.

But Mr Koizumi says he has to, not just for regional peace, but for world stability.

Japan had been demanding answers over its missing citizens as a pre-condition for talks on normalising relations with North Korea.

North Korea had previously denied any involvement in the disappearances.