Update: Tyfine Hamilton surrendered early Friday. In an interview with CBS3, his aunt, Takena Throes, apologized and expressed sorrow to James Stuhlman's family. She said Hamilton was "off" his medications.

Earlier Story:

BRANDON SMITH and Tyfine Hamilton aren't old enough to get their learner's permits. The 15-year-old Overbrook High School freshmen have never been to a prom or walked into a voting booth.

But somehow, they got their hands on a gun, and after a game of basketball in their Overbrook neighborhood last week, they used it to take the life of James Stuhlman, 51, who was out walking his dog, according to police.

"They go from doing things young kids do to doing some things that very bad grownups will do," Homicide Capt. James Clark said. "They go from playing basketball to committing murder."

Now Smith, of 66th Street near Sherwood Road, stands charged as an adult with murder, and police are canvassing the city for Hamilton, whom they believe was the gunman.

A 14-year-old boy, whose identity was not released, was also with the two boys during the commission of the crime, Clark said. That child will be charged in connection with the slaying, but he is cooperating with authorities and will face lesser charges, according to police.

Clark said the boys just "came up with the idea" to rob someone after they finished playing basketball on March 12. They initially planned to rob another dog walker but then they saw Stuhlman, who was walking on Woodcrest Avenue near 64th Street about 8:30 p.m.

"He was a lot older than the first potential victim and as they stated, his dog looked 'weak' or 'soft,' so they went for the second male," Clark said.

Hamilton allegedly pulled out the gun and announced a robbery. There was a brief struggle, during which Stuhlman begged the robbers not to shoot him, but they disregarded his pleas and fired one shot into his chest, police said.

The married father who owned a landscaping-supply business was taken to Penn Presbyterian Medical Center, where he was pronounced dead. The boys took not a single thing from him.

"Nothing was taken, which makes this even more senseless and even more troubling, that nothing was taken at all and he lost his life," Clark said.

Detectives canvassed the area and pored through hours of surveillance video to identify the suspects. On Wednesday, two district cops spotted boys matching the description of the suspects and after a brief foot chase, they were able to arrest Smith and the 14-year-old, Clark said.

Yesterday, Clark urged Hamilton to turn himself in to police.

"Come see us before we come see you," he said. "We know who you are. All of the police in the districts will be looking for you, Homicide detectives will be looking for you.

"Get with your parent and turn yourself in before we come get you."

Hamilton, of Wanamaker Street near Lebanon Avenue, should be considered armed and dangerous. Anyone with information on his whereabouts is urged to call 9-1-1 or the Homicide Unit at 215-686-3134.

There is a $20,000 reward for Hamilton's arrest and conviction.

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