A 15-year-old accused of fatally shooting an innocent bystander last month in Yonkers turned himself in early Tuesday morning. Published reports say Jamir Thompson’s accused of killing 18-year-old Marilyn Cotto Montanez while she and her 9 year-old sister were going to get pizza. Montanez was not the intended target of the shooting. Thompson is being held without bail. As a juvenile offender, he’ll face a maximum of seven and a half years to life in prison on a charge of second degree murder.