PHILADELPHIA (CBS) – Police announced a second 15-year-old has been charged for his involvement in the murder of a man walking his dog in West Philadelphia.

Authorities say on Friday, March 20, Tyfine Hamilton was arrested and charged with murder, criminal conspiracy, robbery, violation of the uniform firearms act and related offenses.

READ MORE: Philadelphia Police: ATV Driver Traveling In Wrong Direction Killed After Crashing Into Vehicle In Holmesburg

Hamilton turned himself into police Friday morning.

Brandon Smith was already charged in the murder of 51-year-old James Stuhlman.

READ MORE: 3 Montgomery County School Districts To Require Masks Again Due To County's COVID-19 Level

Police say James Stuhlman, took his dog out for a walk near his Overbrook home when he was confronted by the teens and fatally shot in the chest.

Authorities say a 14-year-old was also arrested on March 19th and charged with robbery and conspiracy.

MORE NEWS: WATCH LIVE: Delaware County DA To Announce Charges Against Bus Driver Accused Of Taking Illicit Photos Of Teenage Students