A Chilean man went on trial in the eastern French city of Besancon on Tuesday, on charges of having murdered a Japanese student, his ex-girlfriend, in December 2016.

The case has been complicated both by the fact that no body has been found, and by the long struggle experienced by French judges to obtain the man's extradition from Chile.

The accused, Nicolas Zepeda, the son of a wealthy Chilean family, has also consistently denied involvement in the disappearance of the victim, Narumi Kurosaki.

The case has been followed closely in all three countries involved.

What do we know about the case?

Zepeda met Kurosaki in Japan in 2014, and the two began a relationship a year later, with Kurosaki traveling to Chile to meet her boyfriend's family, according to the AFP news agency.

However, their relationship ended when Kurosaki, then 21, went to study in Besancon in August 2016.

Zepeda traveled to Besancon in December of that year and Kurosaki was last seen dining with him at a restaurant near the city on December 4. In the early hours of the next morning, fellow students in the dormitory where she was living heard cries and thuds from her room, though no one initially reported this.

Kurosaki was then not seen for several days, but her disappearance was not reported until Zepeda was back in Chile.

Prosecutors believe Zepeda killed Kurosaki in a jealous rage because the young woman had a new relationship, and say he likely hid her body in a nearby forest.

Long extradition process

Although France issued an international warrant for Zepeda's arrest following Kurosaki's disappearance, a Chilean judge threw out a request to arrest him in February 2017.

Zepeda was, however, finally extradited to France for questioning in July 2020 and charged with murder shortly afterwards. The handover was delayed by coronavirus restrictions and border closures.

Zepeda, now 31, has always denied involvement in the disappearance.

Kurosaki's mother and sister are attending the trial after traveling from Tokyo.