Former Argentine boxing world champion Jorge 'La Hiena' Barrios was arrested on Friday following a complaint by his partner for gender violence, judicial sources said.
The woman, María Muñoz, 33, told police that Barrios, 45, had threatened her life with a gun. The former World Boxing Organisation (WBO) super featherweight champion from 2005 to 2006.
The couple had recently met online, according to sources.
The woman was with her 13-year-old son at the time of the threat, according to the file.
In 2010, he crashed his car into a parked vehicle which, in turn, hit and killed a young pregnant woman in the resort city of Mar del Plata, south of the capital.
The former boxer was sentenced to almost four years in prison for manslaughter, but was released on bail.