German prosecutors have charged a 98-year-old man with complicity in the killing of some 3,300 people in a Nazi concentration camp in World War II, reports the BBC.

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

It is said to have helped in “cruel and insidious” mass killing of prisoners.

Since 2011, Germany has also prosecuted former Nazis for complicity, not just murder or torture.

But it is a race against time, as the defendants were elderly and some died before being tried.

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

Tens of thousands of prisoners died of starvation, forced labor, 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, since the man was a teenager at the time of the crimes. He now lives in Main-Kinzig, a rural district in central Germany.

Last year, a 101-year-old man, Josef Schütz, was found guilty of aiding mass murder in Sachsenhausen. He was sentenced to five years in prison, but died in April this year, still free, pending the outcome of the appeal.