Hello there, welcome to the witness history podcast from the BBC World Service with me, Alex Collins.

Today I'm taking you back to 1990 when an Australian archaeologist unearthed the mass grave.

It's a distressing story.

Richard Wright is in the middle of a pine forest, in Ukraine, in what was then the Soviet Union.

Someone shouts over to him, a shocking discovery has been made.

I went over, jumped down into their hole, and there was a woman skeleton with a plat of hair.

It was blonde and it was down to waist length, a very long plat.

It personalized the skeleton.

I was used to dealing with human bones, but suddenly to see a plat makes that person human in a way that I have forgotten.

And as soon as I saw that plat of hair, I reacted in a bad way, I suppose you could say, because it looked like one of my daughter's plat.

It was the first of more than 500 bodies that Richard and his team would find in the village of Surnicky.

The victims were Jewish people who were murdered by Nazis in the early 1940s during World War II.

How had this Australian ended up over 14,000 kilometres from home?

With this scene of horror in front of him, he'd got a call from the chief medical officer from the Sydney Morgh, Dr. Godfrey Oatley.

The Australian authorities had charged the Ukrainian man who had migrated to Australia with involvement in the mass killing.

Ivan Polyakovich, who lived in Adelaide, was one of hundreds of suspected Nazi war criminals who had moved to Australia after World War II.

The prosecution would need archaeologists to gather evidence.

Dr. Oatley asked Richard to go to Ukraine with him.

Richard agreed and his wife Sonja, also an archaeologist, would accompany him.

At first, the Ukrainian team of forensic people were very helpful.

They thought that we would just want to watch them finding a grave.

But of course, for legal reasons, we had to take part in it.

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