A third boy has now been charged in the slaying of a Philadelphia man who was out walking his dog.

Homicide detectives said Monday that 15-year-old boy who turned himself in Friday is charged with murder, criminal conspiracy, robbery and firearms and related offenses.

Another 15-year-old boy was earlier charged with murder, robbery and related offenses in the case, and a 14-year-old boy was charged with robbery and conspiracy.

Police allege that the three were playing basketball March 12 when they decided to rob someone.

They say the trio targeted 51-year-old James Stuhlman, who was shot to death even though he pleaded for his life.

He was the owner of a suburban landscaping company and took nightly walks with his dog, a labradoodle named Molly.