"Last night another expulsion was carried out for the security of the state," Alfano told Italian media on Friday morning.
The man in question had told police that he was linked to Isis and that he wanted to "cut off Italians' heads", Il Fatto Quotidiano reported. These comments were made when he was arrested for attacking a minor in December; since this incident he had been under investigation.
"After a series of investigations, we confirmed that he was in the process of religious radicalization," Alfano added.
The man in question was a 32-year-old, originally from Morocco, and had moved to Italy in 2013. Since then, he had been living in Potenza in southern Italy.
Italy has upped its security following terrorist attacks on Paris and Brussels in recent months and after receiving threats from the Isis group.
A total of 259 people were arrested on terror charges in Italy in 2015, with 67 of them being expelled from the country as a result. Among these was a Moroccan man, deported in late December after saying he would "blow up Rome". A further nine have been deported since January.