At 10:30 this morning, Boston Police Homicide Investigators along with officers from District 6 went to 178 W. 8th Street in South Boston and arrested a juvenile charging him as a Youthful Offender for Manslaughter.On August 26, 2005, 40-year-old homeless man, Mario Acosta Chavez was found outside 56 F Street suffering from head trauma. He was taken from the scene to Boston Medical Center and was pronounced dead on August 27. His death was ruled a Homicide by the Office of the Chief Medical Examiner. The juvenile was taken into custody at his home pursuant to an arrest warrant, without incident and was arraigned today in Boston Juvenile Court. A second individual, 17-year-old Thomas Grealish of South Boston was charged in August with assault in connection with the attack on Acosta and is currently in custody. The investigation into the incident is ongoing.