A 15-year-old boy was shot in the face in front of his Detroit home Thursday evening after a video game transaction went horribly wrong. His father, watching from inside the house, rushed out and shot the assailant dead, police said.

Police said a preliminary investigation found the teen had arranged to meet up with the suspected shooter, so far described only as a young man, to sell a video game, The Detroit News reported.

A struggle ensued when the young man tried to rob the boy, and he pulled out a gun and shot the 15-year-old, who is in critical condition in the hospital, according to police.

The father, 36, ran out of the house after seeing his son shot and opened fire on the shooter, who was pronounced dead at the scene. He is in police custody but has not yet been charged with a crime. Police said they have 72 hours to prepare a warrant for his arrest, and prosecutors will consider whether to charge him with a crime.

The shooting took place on the 2400 block of Honorah Street on the city’s southwest side. A neighbor told The Detroit News she was shocked to hear gunshots in what she called “a very quiet, very nice neighborhood.” Police recovered two guns at the scene.

In a news conference midday Friday, Detroit Police Chief James Craig provided no new information on the shootings, citing an ongoing investigation. When asked if the father went too far, he declined to give a direct answer but replied, “It depends.”

“There are times when deadly force is appropriate," Craig said, "whether it’s a police officer or a citizen fearing for his life or the life of another.”

Craig has argued that having more civilian gun owners could make Detroit safer.

The conference had been scheduled before the Thursday shootings to correspond with the first day of summer, Craig said, to announce an anti-violence social media campaign he’s calling “Check yourself. Stop the violence.”

He said the campaign will send the terse message through Twitter, Snapchat and Instagram, with the goal of reaching more young people. Asked for more details, a police spokeswoman added that the department will use the hashtag #WalkAway.

Thursday’s shootings were the latest in a string of what Craig called “violence that erupts over senseless things" in Detroit. The chief cited another shooting just a day earlier, when 61-year-old twin brothers allegedly attacked customers and shot a man in the face in a Coney Island hot dog shop in the city after getting angry that the restaurant didn’t have fried mushrooms.

The 40-year-old victim in that case is also in critical condition, Craig said.

“When we look at our homicide picture for this year," the chief said, "while we’re reporting a decline, we know that 31 percent of our homicides are caused by a simple argument.”

He also referenced a recent slaying over a liquor bottle left in a front lawn, as well as the January killing of a 3-year-old boy who was shot in the back seat of a car on the way to see Sesame Street Live after a gunman reportedly thought the child’s godmother had cut him off on the freeway.

“When we talk about preventing violence,” Craig said at the conference, "it starts with who? It starts with you. So stop it.”

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