A 92-year-old former SS guard will go on trial in October charged with helping to murder 5,230 prisoners at a Nazi camp where executioners killed inmates with jabs of petrol to the heart.

In what will be one of the last cases against Nazi-era crimes, Bruno Dey is accused of being a private at the Stutthof concentration camp near Gdansk, in what is today Poland, and of being involved in killings between August 1944 and April 1945.

Although he is not accused of any specific killing, Dey is charged as an accessory to those committed and prosecutors described him as 'a small cog in the machinery of murder'.

Hamburg prosecutors say that in his role as guard he helped prevent prisoners from escaping.

Dey is accused of serving as a guard when he was 17 and 18. Because of his age at the time of the alleged crimes, he will be tried in juvenile court and faces a possible six months to 10 years in prison if convicted.

More than 60,000 people died at the Nazi camp east of Danzig, which today is the Polish city of Gdansk, including Jews, political prisoners, homosexuals, Jehovah's Witnesses and Polish civilians and resistance fighters after the brutal suppression of the 1944 Warsaw uprising.

Prisoners were given lethal injections of petrol or phenol directly to their hearts, shot or starved. Others were forced outside in winter without clothes until they died of exposure, or put to death in a gas chamber.

The wooden main gate leading into the former Nazi German Stutthof concentration camp east of Danzig, which is today the Polish city of Gdansk

One of the last remaining documents relating to the suspect, Brudo Dey's, time at Stutthof which relates to his clothing

The suspect has made a partial confession, said a spokeswoman for the Hamburg prosecutors, but gave no further details. Under German rules for court cases, the suspect's full name is not published.

Die Welt daily reported he had acknowledged his presence at the camp and said he knew that people were pushed into gas chambers and that he had seen bodies being burned in the crematorium. However, he argued this did not amount to guilt.

'What use would it have been if I had left, they would have found someone else?' Die Welt newspaper quoted him as saying.

When he was charged in April, prosecutors called Dey 'a small cog in the machinery of murder'.

'Surveillance was necessary for the concentration camp to function, and the camp was made to kill people,' Hamburg state court spokesman Kai Wantzen said of the prosecution's argument.

Mr Wantzen said the suspect did not deny serving at Stutthof and was aware people were being killed.

Prosecutor Lars Mahnke said that Dey was not a staunch admirer of Adolf Hitler's ideology, but believed he could survive by keeping his head down and following orders.

German authorities have been pursuing cases against former camp guards and others suspected of Nazi-era war crimes more vigorously in recent years, but have been finding prosecutions increasingly difficult due to defendants' ages. At 92, Dey is one of the younger suspects to be brought to trial.

Another former Stutthof guard, Johann Rehbogen, went on trial in November in Muenster at 94 but proceedings collapsed within weeks after the defendant was admitted to hospital for heart and kidney issues.

Following that, a Frankfurt court refused to put a former Majdanek death camp guard on trial after ruling the 97-year-old was too sick to face court proceedings.

Dey, who had been expected to give evidence in the Rehbogen trial before proceedings fell apart, has been deemed fit to stand trial by experts but sessions will be limited to two hours a day, and are scheduled to be held only twice a week, Mr Wantzen said.

Stutthof survivors and relatives are expected to join the Dey trial as co-plaintiffs, as allowed under German law.

The recent prosecutions all rely on new German legal reasoning that being a camp guard is enough to be found guilty of accessory to murder, even without specific evidence of a crime. The argument was first used successfully against former Ohio car worker John Demjanjuk in 2011.

Before that, prosecutors would have to provide evidence a specific guard was involved in a specific killing - often a near impossible task given the circumstances of the crimes committed in camps and the scarcity of surviving witnesses.

Demjanjuk was convicted on allegations he served as a Sobibor death camp guard. He always denied the accusations but died before his appeal could be heard.

The 2015 conviction of former Auschwitz guard Oskar Groening using the same argument was upheld by a federal court, solidifying the precedent.

The Rehbogen trial was the first use of the reasoning to charge and try a concentration camp guard instead of a death camp guard, but prosecutors have expressed confidence it can be applied, since tens of thousands of people were killed in Stutthof, even though the camp's sole purpose was not murder - unlike camps such Auschwitz-Birkenau, Majdanek or Sobibor.