Pittsburgh police probing possible drug link as 3 students are wounded outside high school

This photo provided by the Pittsburgh Bureau of Police Wednesday Nov. 13, 2013 shows Anjohnito Willet arrested as the shooter of three Pittsburgh high school students heading to their vehicle after classes ended. Willett, 16, was charged as an adult and in custody late Wednesday on four counts each of attempted homicide, aggravated assault and reckless endangerment. He's also charged with illegally possessing a gun as a juvenile. (AP Photo/Pittsburgh Bureau of Police) (The Associated Press)

In this aerial image provided by KDKA-TV, a person is loaded into an ambulance near Brashear High School in Pittsburgh, Wednesday, Nov. 13, 2013. Pittsburgh police reported Wednesday that three people were shot near the school. The condition of the person in the stretcher was unknown Wednesday. (AP Photo/KDKA-TV) (The Associated Press)

Police investigators go over the scene, Wednesday, Nov. 13, 2013, near where three students were shot outside a Pittsburgh high school in Pittsburgh, Pa.Pittsburgh school district spokeswoman Ebony Pugh told The Associated Press all three students were shot outside Brashear High School on Wednesday afternoon as they walked to a vehicle they'd all taken to school earlier in the day. Pugh and police spokeswoman Diane Richard said the injuries appear to be non-life-threatening, though their descriptions of the injuries differed slightly. (AP Photo/Gene J. Puskar) (The Associated Press)

Pittsburgh police have charged a 16-year-old student with shooting three others outside a high school, allegedly in retaliation for a drug-related robbery inside the school last month.

None of the students wounded minutes after Brashear High School dismissed classes Wednesday has life-threatening injuries. Police say two were grazed by bullets, while one was shot in the arm and foot. Police say a fourth was targeted but not hurt.

The school, with about 1,400 students, will be open the rest of the week on a modified lockdown, restricting the building to students, teachers and visitors with prearranged appointments.

Police Lt. Kevin Kraus says the alleged shooter, Anjohnito Willett, shot the others as revenge for the Oct. 18 incident. He was in custody Wednesday. It wasn't known if he has an attorney.