Campanella

University student Sara Campanella, 22, was killed by an acquaintance on Monday afternoon in the Sicilian city of Messina.

Witnesses told media that they saw a man - later identified by prosecutors as 27-year-old Stefano Argentino - walk up to Ms Campanella and stab her on the street.

A passer-by who reportedly heard Ms Campanella's screams tried to chase the attacker, who managed to flee.

The Messina prosecutor, Antonio D'Amato, said that Stefano Argentino had "insistently and repeatedly" harassed Sara Campanella since she started university two years ago.

One of her friends once had to intervene when Mr Argentino kept complaining that Ms Campanella no longer smiled at him, Mr D'Amato said.