Tunisian authorities on Saturday have detained a 26 year old man in al Qasreen province on suspicion of aiding and adopting extremist ideologies, police source said on Saturday.
After issuing a prosecution warrant, the police stormed his house and he was arrested in possession of recordings for Salafi ideology and radical Islam books inciting on violence.
 In December, Tunisian security forces have arrested three suspected militants after uncovering their links to Anis Amri, the Tunisian national believed responsible for the Berlin Christmas market attack that killed 12 people, Tunisia's Interior Ministry said on Saturday.
The ministry said Amri's nephew was among the three men and had been in touch by social media messaging with Amri, who was killed on Friday by Italian police after he pulled a gun on them during a routine search.
Seifeddine Rezgui is believed to have acted alone when he killed 38 tourists at the Marhaba Imperial hotel, but security forces have promised to bring to justice those who helped him prepare for the slaughter.
The efforts to trace and dismantle the support network behind Tunisia’s bloodiest attack in recent history, responsibility for which was claimed by Islamic State after the gunman died, have become more urgent amid fears of another massacre.
Authorities believe Rezgui learned how to use his gun at the same jihadi training camp as two men who killed 21 foreign tourists at a museum in March. They fear a third sleeper cell, formed at the same time, could still be lying in wait.
It was not clear if those two were the same men featured on wanted notices earlier this week.