A regional court in the southwestern town of Baden-Baden said it was abandoning an investigation because there was "no doubt" the body found in Cairo was that of Heim, who had changed his identity and converted to Islam.

"The criminal case against Dr Aribert Heim on suspicion of multiple murders has been abandoned because of the death of the accused," the court said in a written statement.

Heim, one of the world's most wanted war criminals, became known as "Doctor Death" and the "Butcher of Mauthausen" after performing medical experiments on concentration camp prisoners.

Besides Mauthausen in Austria, he also served at the Sachsenhausen and Buchenwald camps in Germany.

In February 2009, German public television channel ZDF and the New York Times said that Heim, a former member of the Nazi SS, had died of bowel cancer in 1992 at the age of 78, citing his son and acquaintances in Cairo.

But his death was never confirmed and a report by Der Spiegel news weekly several months later said investigators believed the ZDF and NYT report did not provide "any proof of his death" and they were continuing to examine "every lead" on the Austrian-born Nazi.

The Simon Wiesenthal Centre in Jerusalem also said it did not believe the story.

The Baden-Baden court however said on Friday that it no longer doubted that Heim was in fact a man named Tarek Hussein Farid who died of cancer in August 1992 in Cairo.

The court said it had reached the conclusion after, among other things, the defence for the accused had presented it with documents, including a certificate showing his conversion to Islam.

Together with information provided by his son, there remained "no doubt that the accused is identical to the person Tarek Hussein Farid and died in 1992 after suffering from cancer", it said.

German authorities charged him in 1979 with having "cruelly killed prisoners through injections or unnecessary operations" at the Mauthausen camp in 1941, the court said in its statement.

The court had announced in August that it aimed to establish in the coming months whether Heim was dead after receiving the initial results of the analysis of original documents from Egypt.

In 1945 at the end of World War II Heim was arrested by the US military but he was let go after two and a half years, and he went on to work as a gynaecologist in Baden-Baden.

He pursued his profession in the picturesque spa town for around 15 years but fled in 1962 as the West German authorities were about to arrest him.