Dublin Police Chief Wayne Cain says the 15-year-old told authorities he brought the gun to Dublin High School on Monday for self-protection. Cain says he was putting the gun in his backpack when it went off.

Cain says a bullet fragment ricocheted off the floor, striking the leg of a 17-year-old student, causing a bruise.

Cain says the 15-year-old was being held at a Youth Detention Center pending a hearing. He says the gun belongs to a family member.