Some 400,000 German children were born after World War II whose fathers were occupation soldiers, historians said in Vienna on Thursday, presenting figures far higher than previous estimates.

At the first historical conference to be held on the topic, scholars and so-called war children called for government help in looking for fathers whose identity or whereabouts are still unclear in many cases.

"These children feel they are incomplete all their lives," said Silke Satjukow, a historian at Germany's Magdeburg University.

She said that many have been approaching scholars to seek support. "We can help them in some ways, but it's not really our competence," she added.

Researchers had previously assumed that there were 68,000 such children in Western Germany and 8,000 in Austria, born to allied soldiers from Britain, France, Russia and the United States. No estimates existed for Russian-occupied Eastern Germany.

The current estimate is 100,000 in Western Germany, 300,000 in the East and 40,000 in Austria, according to Satjukov.

A majority of these children were fathered when soldiers raped German and Austrian women, but there were also many real relationships between occupiers and occupied in the former Nazi countries.