STORY: Esther Fuxbrumer holds up a photo of twin girls.

"These are Yehudit and Ruth Rosenbaum from Romania, that were twin girls, four-and-a-half years old, that were in like a smaller group under Mengele's (Nazi doctor Josef Mengele) group in Auschwitz. Yehudit survived, Ruth was killed, was murdered."

Ruth is one of the more than six million Jews murdered by the Nazis during the Second World War.

Until recently, very little was known about her.

Fuxbrumer is part of a team of researchers at the Yad Vashem World Holocaust Remembrance Centre in Jerusalem who are trying to fill the gaps in existing records.

Using artificial intelligence, they have been able to step up the search for details of unknown and known victims, like Ruth.

"And we were able to bring more information about Ruth from someone that's not her family at all, someone that met her in the camp. And we believe that way we'll be able to bring a lot of stories about a lot of victims that were killed, little kids that no one else knew, to tell us the story about what happened to them."

The AI-powered software sifts through records in English, Hebrew, German, Russian and other languages.

Over the years, volunteers have tracked down information on 4.9 million individuals by hand...

by reading through statements and documents, checking testimonial film footage, cemeteries and other records.

Then there's the mammoth task of linking people to dates and family members while watching for duplicates and comparing accounts.

Fuxbrumer says AI streamlines the process - and removes human error.

"That technology works very fast, it takes a few hours to go over hundreds of testimonies and it's very exact, the results. A human being wasn't able to do it." // "We saw that from each testimony we could get between six or seven names with full details that we could put automatically into our database, and around 10% of the names that we found we had already in our database, but 90% are new names that we didn't know about."

Fuxbrumer says 1,500 new names have been added to their records, and many more are expected in the coming weeks as the system gets through all 30,000 testimonies.

"There are lots of people that were murdered and no one knows about them, and there were people like me and you that lived here and had feelings and had lives and were happy and wanted to live. And it's very important to remember every name of them, each one and one of them."