A gas chamber at the former Nazi German concentration camp, Stutthof near Gdansk, Poland Bruce Adams-Pool/Getty Images

German prosecutors investigating Nazi-era crimes say they have charged two former SS officers with complicity in the murder of hundreds of people at a concentration camp.

Both men, now aged in their 90s, served as guards at the Stutthof camp, located near what is now the Polish city of Gdansk, investigators said on Wednesday (15 November).

The indictments were filed against a 93-year-old man from Borken, who served in Stutthof from June 1942 to September 1944, and a 92-year-old man from Wuppertal, who was there from June 1944 to May 1945.

Both men deny they had any knowledge of killings at the camp, Dortmund prosecutor Andreas Brendel said.

About 65,000 people died at Stutthof. Some were put to death in gas chambers or shot, while others died from malnutrition or froze to death.

The men, who have not been named, both served as guards and also watched over prisoners who were taken outside the camp to work. During the time they were at Stutthof, hundreds of killings occurred.

Members of the SS killed more than 100 Polish prisoners and some 77 Soviet prisoners of war in the camp's gas chamber in 1944. An unknown number of Jews also were gassed there in late 1944.

Between June 1944 and April 1945, SS members also killed several hundred Jews by shooting them in the back of the neck. SS-physicians and nurses at Stutthof killed more than 140 prisoners, many of them Jewish women and children, by injecting their hearts with gasoline and the chemical compound phenol from late 1942 until late 1944.

"The prosecutors assume that the accused were aware of the different killing methods ...and that such a multitude of people could have only been killed with such regularity because the victims were guarded by helpers like them," a court in Muenster wrote in a statement issued Wednesday.

The two men therefore willingly supported several hundreds of killings of camp inmates in their function as guards, the statement added.

The defendants are just the latest former Nazi prison guards to be pursued by German prosecutors.

Last month, a 96-year-old man was also charged with complicity in the Nazis' murder of Jewish detainees while working as a guard at Madjanek concentration camp in then-occupied Poland.

Prosecutors in the German city of Frankfurt said the man "knew about the cruelty of the organised mass killings" at the camp and that the prisoners "facing their fate, innocently and defencelessly, were killed for inhumane reasons".