A German court has dropped a case against a former Nazi concentration camp guard after finding the seriously ill 95-year-old was unfit for trial.

Johann Rehbogen was accused of complicity in mass murder at the Stutthof camp near what was then Danzig, now Gdansk in Poland.

His trial began on November 6 but was suspended in December as he suffered from serious heart and kidney problems.

Given the gravity of his ailments, the court in Muenster ended the case, deeming him 'permanently unfit for trial'.

Johann Rehbogen, 95, (pictured on November 6) was accused of complicity in the murders of several hundred Stutthof camp prisoners between 1942 and 1944 when he was a guard there

His trial was repeatedly interrupted as he suffered heart and kidney problems, and the case against him has now been dropped after he was ruled permanently unfit

Rehbogen was aged 18 when he began serving as a guard at the Stutthof camp in June 1942. He left the camp in September 1944.

The German, from the western district of Borken, North Rhine-Westphalia state, was charged with being an accessory to the murders of several hundred camp prisoners.

These included more than 100 Polish prisoners gassed in June 1944 and 'probably several hundred' Jews killed from August to December 1944 as part of the Nazis' so-called 'Final Solution'.

He broke down in tears at the trial opening and subsequently told the court he was ashamed of having been in the SS.

Rehbogen however insisted that he was unaware of the systematic killings at the camp.

Rehbogen's lawyer told the panel of judges in one session that while he served at Stutthof, he was 'not a Nazi.'

More than 60,000 people were murdered at the Stutthof death camp by the Nazis, though Rehbogen claimed to know nothing about the mass executions

The case against Rehbogen was among the last to be brought against former Nazi death camp guards because the majority have since died

He suggested that he knew prisoners were being mistreated, but denied any knowledge of the camp's gas chamber or any participation in killing them.

'As a Christian it was hard for me to be part of all of it,' Rehbogen told the court. 'But I was too scared to protest.'

The cases have resurfaced since the legal basis for prosecuting former Nazis changed in 2011 with the landmark conviction of former guard John Demjanjuk.

He was sentenced on the grounds that he served as a cog in the Nazi killing machine at the Sobibor camp in occupied Poland, rather than for killings or atrocities linked to him personally.

German courts subsequently convicted Oskar Groening, an accountant at Auschwitz, and Reinhold Hanning, a former SS guard at the same camp, for complicity in mass murder.

Both men were convicted at age 94 but died before they could be imprisoned.

Their trials will be among the last of former SS personnel accused of being complicit in the Holocaust, because most of the perpetrators have since died.