Hilde Michnia is also alleged to have forced prisoners on an evacuation march at Gross-Rosen in 1945 when 1,400 women died

German prosecutors announced on Monday yesterday they had opened an investigation into a 93-year-old woman suspected of forcing prisoners on an evacuation march in 1945 during which about 1,400 women died.

Hamburg prosecutors’ spokesman Carsten Rinio confirmed that his office had begun investigating Hilde Michnia last week, after a social worker from the northern town of Lüneburg filed charges against her.

She is suspected of serving as a guard in the Bergen-Belsen and Gross-Rosen concentration camps, and having been part of evacuating the latter camp in 1945. Nearly three-quarters of the 2,000 female prisoners forced onto the march are thought to have died.

Hans-Jürgen Brennecke filed the charges after seeing the Irish documentary Close to Evil, aired on RTE last September, in which Bergen Belsen survivor Tomi Reichental attempted to interview Michnia. In the documentary, Michnia admitted to taking part in the evacuation.

“She said herself, three times, ‘I was on the death march.’ I thought, hang on, there have to be some consequences if such important information is in [the film],” Brennecke, who organised the first German screening of Close to Evil last week, told the Guardian. “When I realised that no one had done anything yet, I thought: this can’t be.

“It bothers me that so much is still kept silent, or misrepresented.I just want the facts to come out. Everyone is allowed to have opinions, but we need to know the facts. We’re still not finished with it.”

Michnia, called Lisiewicz during the second world war, has previously been convicted for her work as a concentration camp guard. She was one of a group 45 SS guards put on trial by the British occupying forces in 1945. Survivor Dora Almaleh testified that Michnia had beaten two men for stealing turnips from the kitchen, and Michnia was sentenced to a year in prison and released in November 1946.

In an interview with Die Welt newspaper published last weekend, Michnia dismissed the 1945 proceedings as a “show trial”, and said she had not seen any atrocities, because she had only ever worked in the kitchens. “I didn’t see any of it,” she told the paper. “That was all in a completely different part of the camp.”

When Die Welt asked her if she knew she was under investigation, she reportedly replied: “No, but they won’t find anything.”

Michnia’s case is one of a series of cases of late justice the German judiciary is currently visiting on surviving members of the SS. Lüneburg state court said on Monday that the trial of 93-year-old Oskar Gröning, the so-called “accountant of Auschwitz” charged last year with accessory to 300,000 murders, would begin on April 21.