Young Puerto Rican boxer Alexander "El Pollo" de Jesus was shot multiple times and killed on a street in San Juan's Hato Rey district, where he lived.
Police said on Sunday the body of the 33-year-old fighter was found on Belmonte Street after he was taken by force from his home nearby, reports Efe.
According to the local dailies, a few hours earlier on Sunday the boxer, who represented Puerto Rico in the 2004 Athens Olympics as well as in many other international competitions, had been accused in absentia of mistreating an elderly female neighbour.
Local authorities have asked for the public's cooperation in trying to identify his killers.
De Jesus won medals at the Central American and Caribbean Games in Sal Salvador in 2002 and at the Pan American Games in Santo Domingo the next year.
When he launched his professional boxing career in 2005, De Jesus won his first 19 bouts before suffering his first defeat in 2009 at the hands of Argentina's Cesar Rene Cuenca.
Later that year, he was sentenced to four years in prison for domestic violence against his wife and children. While serving his sentence, he received special permission to face countryman Jose Angel Roman in the ring in 2010, defeating him easily.
He tried to resume his professional career when he was released from prison in December 2013. In February 2015, De Jesus won a unanimous decision against Javier Garcia, although he had lost a fight the month before.
His final career tally was thus 21-2 with 13 knockouts.