German 'Masked Man' serial killer sentenced to life in France for 2004 murder of 10-year-old Jonathan

Verdict in Nantes

A French court in Nantes sentenced 55-year-old German national Martin N. to life imprisonment on 4 June 2026 for the 2004 murder of ten-year-old Jonathan C. The defendant, known in Germany as the 'Masked Man' (Maskenmann), stood motionless as the verdict was read, according to multiple French media reports. He had denied the charge throughout the two-week trial, telling the court, "I did not do it."

The murder of the boy bore the 'criminal signature' of the defendant.

The prosecution had argued that numerous pieces of circumstantial evidence pointed to N.'s guilt, and the court agreed, handing down the maximum penalty.

The 2004 disappearance

Jonathan vanished during the night from a school camp in Saint-Brévin-les-Pins, a coastal town in western France. His body was discovered roughly six weeks later in a pond about 30 kilometres away. The boy was found unclothed, bound, and weighed down with a concrete block of approximately 20 kilograms.

A double life in Germany

Between 1992 and 2001, N. abused numerous young boys in northern Germany, murdering three of them, aged eight, nine, and thirteen. He worked as a child carer and educator, leading holiday camps and working in children's homes by day. At night, he would don a dark balaclava and creep into the bedrooms of his victims, earning him the 'Masked Man' moniker.

In February 2012, the Stade Regional Court sentenced him to life imprisonment with a finding of particular severity of guilt. He had confessed to most of the German crimes after an eleven-hour conversation with two police officers.

The French investigation

French investigators began examining potential links between N. and Jonathan's case as early as 2008, noting clear parallels with the northern German series. No direct forensic evidence, such as DNA, was recovered. However, a witness reported seeing a car with German licence plates near a pond on the evening of the disappearance; the driver appeared to be unloading something before driving away. In 2017, a fellow inmate claimed that N. had confessed to killing a child in France.

Psychiatric and judicial cooperation

During the Nantes trial, the court heard from French and German investigators as well as psychiatric experts who had examined the defendant during a temporary transfer to a French facility. The cross-border judicial cooperation allowed the French court to build its case despite the absence of a confession or forensic evidence.

Custody status

N. was born in Bremen in 1970 and is a former child carer and single foster father to a son. He is currently serving his German life sentence in Celle. The new French sentence adds a further layer of legal consequence for a man whose crimes spanned two countries over more than a decade.