According to police sources yesterday, the robbery was carried out in the early hours of November 7.
At 3.30am, the suspect is alleged to have flagged down the taxi and, once in the back of the cab, drawn out a seven centimetre knife and held it to the taxi driver's throat, slightly cutting the victim's neck in the process. The attacker then fled with the driver's mobile telephone and 85 euros.
The police managed to trace the mobile to a woman who, when questioned by the police, claimed to have bought the phone from a young man in the red light district. The police followed the lead and eventually located him on Wednesday.