German prosecutors have charged a 98-year-old man with complicity in the murder of some 3,300 people at a Nazi concentration camp in World War Two.

The man, not yet named, was an adolescent when he served as a guard at Sachsenhausen between July 1943 and February 1945, the indictment says.

He allegedly assisted in the “cruel and insidious” mass killing of inmates.

Since 2011, Germany has prosecuted ex-Nazis for complicity – not only for murder or torture as individuals.

But it is a race against time, as those indicted have been very old and some have died before going on trial.

The Nazi SS imprisoned more than 200,000 people at Sachsenhausen, including political prisoners, Jews, captured Soviet soldiers, Roma and Sinti (Gypsies).

Tens of thousands of inmates died from starvation, forced labour, medical experiments and murder by the SS. The camp was built north of Berlin in 1936.

In the latest prosecution, the case will be handled by a juvenile court, given that the man was an adolescent at the time of the crimes. He now lives in Main-Kinzig, a rural district in central Germany.

Last year, a 101-year-old, Josef Schütz, was found guilty of assisting in mass murder at Sachsenhausen. He was given a five-year prison sentence, but died in April this year, still free while awaiting the outcome of an appeal.