The Sofia City Court is due to sit on an extradition request for Mourad Hamyd, a man man sought in France who was detained in Bulgaria last week.

French media have reported that Hamyd is a brother-in-law of Ch?rif Kouachi, one of the perpetrators of the terror attack on Charlie Hebdo satirical newspaper in Paris last year. For a brief period he had been suspected of complicity to the attack, but investigators deemed his alibi to be solid enough.

Hamyd arrived in Bulgaria on July 26 at 19:45 and tried to leave on July 28 at 01:30. It was not immediately clear how he spent more than 48 hours in the country. Bulgarian authorities alerted their French counterparts of his arrival as he had been declared missing by his sister.

He was initially detained at the border between Bulgaria and Turkey, after crossing it successfully but being sent back by Turkish border police. The reason was that he had been barred from entering Turkey for five years. Shorly after his detention, official reports were submitted to Bulgarian border police about his alleged terror link and affiliation to the Islamic State (IS) group.

On July 29, he was placed in detention in the Bulgarian capital Sofia under a European Arrest Warrant which was received from French authorities on that day.

It was Mourad Hamy's sister, Khadija, who told police her brother had departed to Bulgaria by train, crossing Hungary and Serbia, despite explaining to her he was willing to go to Morocco. French authorities responded by issuing an arrest warrant.

The Bulgarian Chief Prosecutor's spokesperson, Rumyana Arnaudova, cited on Monday data from the national counter-intelligence authorities which described him as a "genuine, present and grave threat to our national security." In her words, international intelligence had also revealed him as a traveling IS fighter.

The defense, however, says Hamyd is a science student who travels for tourism purposes and his case should not give ground to "public hysteria" as to his personality and as to what activities he carried out in Bulgaria.

The 20-year-old man has already said he will agree to be handed over to French authorities, his court-appointed attorney Dragomir Aleksandrov has told AFP.